The Middle Corridor is more than a sanctions-proof trade route between the Russian Federation and Iran. It is a strategic space where two wars intersect, sustaining Western supply chains while quietly feeding the Russian economy. The July 25 Ukrainian drone strike on an Iranian vessel exposed how fragile this balance has become.

The significance of the event is deeper, as while trade flows may find a way, investment in the region’s connectivity could suffer. Tehran is persistently refusing to ratify a 2018 agreement on the status of the Caspian Sea, which it signed onto in 2018. Therefore, Iran follows a “nothing is agreed until everything is agreed” policy line, demanding to settle oil and gas exploration rights in a single package deal with the delimitation of territorial waters and fishing zones. The result is insecurity, which could have a significant effect on international investment.

To discuss the safety, security, and instrumentality of the Middle Corridor, as well as the security of the Caspian Sea more broadly, Caucasus Watch reached out to Eldaniz Gusseinov, a Kazakhstan-based geopolitical expert and co-founder of Nightingale International.

With the July 25 strike on an Iranian vessel in the Caspian Sea, this was not the first attack of its kind on vessels perceived as playing a role in Russian supply chains. Do you think this issue presents an enduring challenge for the Middle Corridor, or is it a “misunderstanding,” as the foreign ministries of Iran and Ukraine now indicate?

I think this will be an enduring challenge. The tension between Ukraine and Iran is palpable. While Iran is not seeking Ukrainian targets elsewhere, this attack near Astrakhan (roughly 5 km from the Volga entrance to the Caspian Sea) can trigger reprisals. What crossed the threshold was the flag and the casualty: one sailor was killed and others injured. That was the first Iranian casualty under Ukrainian fire. Some of the damage cannot be undone. Such attacks can trigger a sudden rise in insurance costs for shipping. The fact that it’s possible is now established and, therefore, it can happen again. It will be factored in, at a cost.

The fact is that we have two ongoing wars that intersect in the Caspian: Russia and Ukraine, Iran and Israel. Russia will want to keep using the Caspian Sea to ship military equipment and commodities. Iran is likely to cooperate. One of the reasons is that neither Azerbaijan, Kazakhstan, nor even Turkmenistan would be keen to facilitate the overland transit of war materials and certain kinds of goods through their territory. The Caspian Sea is less easily monitored. Seaborne shipments that support a military effort can be “ghosted.” That is why trade of this kind bridging Iran to the Russian Federation is likely to persist.

In November 2020, the Russian government created the Caspian Cluster in the Astrakhan Region by establishing a port special economic zone at Olya and merging it with the existing industrial SEZ Lotos. Iranian companies have also acquired a significant position in Astrakhan’s port infrastructure: Nasim Bahr Kish, an Iranian shipping-related company associated with the Islamic Republic of Iran Shipping Lines, holds approximately 53–54% of PJSC Astrakhan Port, commonly referred to as the Solyanka port. Reported investment commitments or expenditures have exceeded 726 million rubles. Separately, Roza LLC, a subsidiary of Iran’s Golrang Industrial Group, is constructing a household-chemicals plant in the Lotos SEZ. The plant was not yet operational as of August 2026.

Tehran was scheduled to hold a convention on the Legal Status of the Caspian Sea on August 12. Iran is the only state that has yet to ratify the 2018 agreement on the legal status of the Caspian Sea. To what extent is that a business risk?

Iran’s Supreme Leader, Mojtaba Khamenei, has alluded to Iran’s strategic intention to geographically expand the range of U.S. targets. That puts the Caspian Sea in the frame, where there is a significant concentration of Western assets.

Azerbaijan’s Araz–Alov–Sharg project provides the clearest precedent for a military confrontation over disputed Caspian offshore energy resources. On 23 July 2001, Iranian military aircraft and a naval vessel confronted the Azerbaijani seismic-survey vessels Geofizik-III and Alif Hajiyev, which were conducting BP-operated exploration work in the Alov structure. The warship ordered the vessels to leave, and BP suspended exploration for security reasons. The PSA, signed in 1998, subsequently remained dormant because of the unresolved Iran–Azerbaijan dispute over southern Caspian delimitation. A February 2010 U.S. diplomatic cable reportedly referred to Iran’s positioning of the Alborz semi-submersible rig in disputed waters. In 2016, SOCAR and the consortium partners abandoned or terminated the long-frozen Araz–Alov–Sharg PSA.

Against this backdrop, hopes were pinned on the summit of the Caspian states, which was scheduled to take place in Tehran on Caspian Day, August 12, 2026. The expected meeting in Tehran did not happen. The Iranian official statement was that a meeting of high-level officials from the five littoral states will take place on September 23, announced by Deputy Foreign Minister Kazem Gharibabadi on 11 August, who asked the littoral states to ensure the gathering is held at an appropriate level, so the level is not yet fixed.

The related Conference of the Parties to the 2003 Tehran Convention, which entered into force on 12 August 2006, has been given two dates by two Iranian officials in the same week: 23 September by the ambassador to Turkmenistan and 1 October by Gharibabadi. Turkmenistan has separately proposed a summit in Ashgabat on 9 October on falling water levels, which Iran supports.

Bottom line: in my view, this agreement is likely to be ratified as it also serves key Iranian interests. Pezeshkian's cabinet held an urgent meeting to approve the bill on 22 July and sent it to the Majlis. This was taken up by the National Security and Foreign Policy Committee with no plenary vote as of mid-August. Hardline commentators are campaigning against ratification. The media is split: some voices are defending the draft legislation; others want ratification after an agreement on oil and gas exploration rights. The government’s position is that ratification has no effect on seabed delimitation, which relates to the adjacent coastal states.

Another key point in the agreement is Article 3, which stipulates that armed forces that do not belong to littoral states are forbidden from the Caspian Sea, with no possibility to extend permission for operations against the Parties. Gharibabadi restated on 11 August that the five oppose any military presence by non-littoral states and that regional security should be managed by the coastal states alone.

In sum, even if Tehran did ratify the 2018 agreement, this would not be the end of the story. Iran needs to bilaterally settle the question of sovereignty over the seabed with Azerbaijan and Turkmenistan. The delimitation of the perimeter within which a state can drill will remain contested.

Interestingly, Iran’s opposition contests this treaty, siding with hardline opposition. Pahlavi articulated an objection to the ratification on August 6, suggesting the process was not transparent, against Iranian interests, and against historic rights.

The mathematics underpinning the calculation of Iranian rights is worth singling out. Iran’s share of the coast is roughly 11 to 13 percent. The 20 percent figure Iran quotes is founded on post-Soviet negotiations rather than its geographic entitlement. The claim to a 50 percent share is grounded on Iran’s 1921 and 1940 treaties with the USSR. That is the principalist argument.

In sum, there are economic and political dimensions to this challenge. The U.S. blockade of the Strait of Hormuz and the disruption in oil and gas supply chains in the south are motivating Tehran to prioritise oil and gas resources in the South Caspian Sea.

The broader political issue is the historical nature of the dispute. In 2018 Tehran was eager to settle disputes and move on. Then the first Trump Administration imposed sanctions. Currently, both Kazakhstan and Azerbaijan are building deeper ties with the West that Iran perceives as threatening. Just consider that Israel’s President was visiting Astana in April 2026. Overall, the U.S. neighborhood policy piles pressure on Iran.

If trade transiting through the Caspian Sea is less easy to monitor and, therefore, presents littoral states with fewer challenges in enforcing sanctions, what are the chances that overland transit hubs – railway connections – from Russia to Iran will be completed any time soon? It has been a minimum of four to five years that we expect the completion of a railway connection from Russia to the Azerbaijani network, to allow for train transit to Iran. How much longer do you think?

It depends on the development of the Russian-Azerbaijani relationship. What we see now is that Russia is using its relationship with Iran and Afghanistan to remain a necessary power broker and mediator in the South Caucasus and Central Asia.

For Russia, connectivity in the region is critical, economically and for security reasons. If the bilateral relationship between Baku and Moscow is smooth, the Rasht-Astara railway connection will be completed. Russian Energy Minister Tsivilyov said on 18 February 2026 that practical implementation would begin on 1 April, with land registration and compensation settled, Caspian Service as contractor and Iran’s CDTIC as client. In December 2025 Pezeshkian said that the land had been secured for 100 km of the 160 km project.

Iran is fully committed and is promoting overland Eurasian connectivity, not least with Afghanistan, where the 225 km Khaf-Herat line has been operational since 2020 but was built in four segments. The line was damaged and looted after 2021. Its final segment was completed in March 2026 under a $23.4 million Iranian contract. There are now talks for a new line from Herat to Mazar-i-Sharif; this was agreed by Afghanistan, Iran, and Türkiye on October 22, 2025, at the International Union of Railways assembly in Istanbul. A $10 million feasibility study was submitted in March 2026, and cargo shipments are scheduled for March 2027. The plan envisages an additional road connection linking Kyrgyzstan, Tajikistan, and even China via Afghanistan and Iran.

The overall vision is reduced dependence on the Strait of Hormuz for trade. These projects have become a focal point in the framework of the Shanghai Cooperation Organisation (SCO). Promoting Eurasian connectivity is reducing dependence on seaborne trade that can be affected by the United States.

This kind of overland connectivity appears entirely predicated on Chinese capital. Who else would commit capital among international investors?

Russia has pledged 1.3 billion euros of the €1.6 billion Rasht-Astara contract as a state loan, to be repaid over ten years at 3% interest, with Iran covering the balance. I think it’s plausible to expect it will be completed, enabling the strategic connection between Russia and Iran. Strategically, Russia is developing all three North-South routes.

First, there is the eastern branch, running overland from Russia through Kazakhstan and Turkmenistan toward Afghanistan and potentially Pakistan. This includes the Trans-Caspian section, which is the maritime leg between Russian and Iranian ports, and the western branch through Azerbaijan.

One should recall that when Iranian drones struck the terminal of the Nakhichevan International Airport (and a school in the village of Shakarabad on 5 March 2026), injuring civilians, there was a flurry of communication between President Aliyev and President Pezeshkian, as well as between Foreign Ministers Bayramov and Araghchi. Azerbaijan’s critical position as a transit hub between the two countries was no doubt raised. Indeed, Baku suspended truck traffic at every crossing with Iran, issued a NOTAM closing its southern airspace, and ordered its embassy in Tehran and consulate in Tabriz to evacuate staff. Four days later (March 9), Baku reopened the crossings for all cargo. Apparently, in a call by Pezeshkian to Aliyev on March 8, the Iranian President denied all involvement and promised an investigation.

This incident may also be seen as an example of how Russia can leverage its relationship with Iran to project the image of a security provider in the South Caucasus and Central Asia. Lavrov does not miss an opportunity to offer assurances that Iran will ratify the Convention on the Legal Status of the Caspian Sea, pressing Tehran to complete ratification. Meeting Araghchi at the SCO gathering in Kyrgyzstan on July 24 (one day before the strike), Lavrov underscored Russia’s role as a security guarantor, leveraging its position as Iran’s sole supporter in the war against Israel and the United States.

Part of the appeal of the Middle Corridor in the West is that it circumvents both Russia and Iran. This corridor looks critical for the connectivity, first, of Central Asia with the West. But this corridor is also critical for the Russian economy. What is more significant in terms of trade?

It’s a good question. Just look at the growth of volume along the Middle Corridor and where products come and go. The transport of critical minerals from Central Asia is critical for the military industry of Europe and the United States, which as you know needs to be building stockpiles. The supply of antimony is a good example. The US Geological Survey (USGS) ranked Tajikistan among the top three producers in 2023–2025, with output around 17,000 tonnes in 2024 (roughly 16–17% of world production) and 22,000 tonnes in 2025 (about 20%). That means Tajikistan is third behind only China and Russia.

U.S. reserves are modest, around 60,000 tonnes. Furthermore, Tajikistan has attracted foreign investment in antimony processing, including by US-linked operators such as Comsup Commodities at the Anzob plant. Tajik ore and concentrate still go mainly to China and unwrought metal and powders chiefly to France and Belgium. Turkey is also active in the mining and processing of antimony.

Another mineral critical for the defence industry is tungsten, from Kazakhstan, where the first concentrate exports began in 2025 (3,700 tonnes worth about 71 million US dollars). All this quantity was exported to China. The US-facing assets, Northern Katpar and Upper Kairakty in the Karaganda district, are held by Cove Capital, a U.S. joint venture with the National Mining Company of Kazakhstan (70-30% ratio), backed by a US EXIM letter of intent for production of up to $900 million US dollars and a DFC letter for up to 700 million. A tungsten flow to the United States along the Middle Corridor is therefore projected rather than actualised.

In a worse-case scenario, Iran could seek to disrupt such flows. Then there is the issue of the Caspian Sea, ownership and resources. If supplies to Russia continue via the maritime route, Russia is motivated not to upset the status quo and to maintain a secure and stable trade route. If not, then not.

Correct me if I’m wrong. When it comes to the volume of trade, Russia is more important, but the strategic quality of the transiting goods from Central Asia makes this route vital to the West, including the military-industrial complex.

The corridor is very important for the West because it secures supplies of precisely the minerals required to supply the Western military complex. Also, this route is significant for Western nuclear value chains. Kazatomprom told the World Nuclear Symposium in September 2023 that 58 percent of uranium shipments from Kazakhstan to Western customers in the first half of that year moved along the Trans-Caspian International Transport Route. However, a peer-reviewed assessment published in 2025 still described rail through Russia to St Petersburg as the preferred route and Trans-Caspian use as comparatively rare.

It’s not only Russia. It is almost everyone except Iran that is interested in this Middle Corridor: China, Russia, Central Asia and the European Union. And it’s not only about the military-industrial complex: Central Asia supplies other materials that are critical for the European Union and U.S. economies, such as tantalum and beryllium, processed at the Ulba Metallurgical Plant in Öskemen. That plant is the world’s leading producer of beryllium, tantalum, niobium, and molybdenum, spearheading exports from Kazakhstan to Belgium. These minerals are critical to European industry.

For China, these corridors go deep into Central Asia and the Caucasus and enable market access. The route is becoming more important given the disruption of the Northern Corridor, from China to Germany via Belarus and Poland. Poland closed that border on 11 and 12 September 2025 for the Zapad exercises, halting roughly 90 percent of EU-bound Chinese rail cargo and stranding more than 130 freight trains at Brest on a corridor worth about 25 billion euros a year. They reopened the corridor on September 25, after thirteen days. The closure ended, pointing to fragility. Operators at the time turned to the southern route through Kazakhstan and the Caspian, which switched from an emergency solution to the sole available service. In sum, when cargo gets stuck at the border, it needs to be diverted. Everyone has a stake.

Interview conducted by Ilya Roubanis for Caucasus Watch