While the situation around the Strait of Hormuz remains difficult to predict, there is now some clarity on another of Iran's maritime fronts. Tehran has unexpectedly launched the ratification process for the 2018 Convention on the Legal Status of the Caspian Sea. A reasonable question arises: why did it take so long?
Let us recall once again that the convention was signed on August 12, 2018, with its anniversary marked just recently. And only days ago, Iranian President Pezeshkian submitted the law on ratification of the convention to parliament. After eight years of silence, there is suddenly a sense of urgency.
This case somewhat resembles the situation with the Treaty on Comprehensive Strategic Partnership between Russia and Iran. The two sides signed the document on January 17, 2025, and the Russian parliament completed its ratification procedures three months later. The Iranian parliament, however, only began the process shortly before the start of the US military operation against Iran in June 2025.
It is possible, of course, that this case simply involved some kind of bureaucratic delay. People in the East are not generally fond of rushing things. Still, the coincidence is suspicious. But what is six months compared with eight years? There was clearly a strong reluctance in Iran to accept the common position of the Caspian states.
A Brief Look Back at the Caspian Sea's Legal Status
The process began with the collapse of the Soviet Union, when a new reality emerged on the Caspian. Instead of two states — the USSR and Iran — there were suddenly five:
- Kazakhstan
- Azerbaijan
- Turkmenistan
Given that the Caspian Sea is a rich oil and gas region, most of the coastal states immediately began developing its natural resources. At the same time, there was no clear division of the Caspian Sea's territory. The countries negotiated on a bilateral basis. Iran, meanwhile, was not particularly concerned about oil and gas production in the Caspian itself, as it had plenty of other deposits.
Nevertheless, the Caspian's legal status still needed to be settled. The countries needed to develop new principles and rules that would satisfy all five states. Long consultations and negotiations began and ultimately lasted for roughly a quarter of a century. Only in 2018 did the countries sign the convention.
It would seem that such a long period should have been enough to resolve all the contradictions. And outwardly, that was how things appeared. But it later emerged that of the five countries that signed the agreement, only Iran had failed to complete all the necessary procedures, putting the matter on hold for a full eight years.
At least, that is how it appears. In reality, Rouhani, who was Iran's president when the convention was signed, pointed out that the convention resolved neither the division of the seabed nor the allocation of the Caspian's surface area. Rouhani saw the convention's role only in establishing general principles for security, navigation and environmental issues. That in itself was no small achievement. Everything else, he argued, had to be agreed upon through further negotiations.
Iran's Position on Its Share of the Caspian
Under the provisions of the convention, Iran would receive only 13% of the Caspian Sea, the smallest share of all the coastal states. Tehran, however, proposed treating the Caspian not as a sea but as a lake, arguing that all five coastal states should receive equal 20% shares.
There is no complete unity on this issue even within Iran. The most maximalist position on the division of the Caspian is held by the conservative part of the political elite, particularly the senior clergy, the Islamic Revolutionary Guard Corps and a significant portion of parliament. Moderate politicians, who are more closely associated with the reformist wing, are more inclined to accept the principles of the convention. But again, this division is quite conditional.
Still, it is worth asking how achievable this maximalist goal actually is, given that Iran stands virtually alone among all the Caspian states in its position.
When Iran signed the convention in 2018, it presumably acted out of security considerations. By that time, close military and political cooperation had developed between Azerbaijan and Turkey. Tehran had also begun to suspect Baku of intelligence cooperation with Israel. In this context, the Caspian Sea could have become an area of operations for extra-regional actors against Iran. Especially since such plans had been under consideration for a long time.
Back in 1994, the Clinton administration declared the Caspian an area of its national interests.
Western oil companies such as Chevron and British Petroleum appeared on the Caspian. The situation went so far that in 2003 the United States considered implementing a plan called "Caspian Guard,” which envisaged deploying special units and bases for maritime special operations along the Caspian coast. All of this was supposedly intended to protect its economic assets.
Russia and Iran managed to halt this process through joint efforts. And to prevent similar incidents in the future, the 2018 convention specifically established the principle of prohibiting the presence of armed forces belonging to extra-regional states in the Caspian.
But in 2018, Tehran said "A” for some reason without saying "B.” As a result, an unclear situation emerged in which some countries followed the principles of the convention regardless of Iran's position. Others, meanwhile, continued to conduct joint naval exercises with countries that had no direct connection to the Caspian.
And now, eight years later, Iran has finally begun considering ratification of the Caspian convention. Yet if Iranian public channels are analysed, many view Pezeshkian's decision almost as an act of capitulation, or even as a betrayal of national interests. At the same time, there is a view that Moscow somehow influenced the shift on this issue.
Perhaps it did, and perhaps it did not. But how could Russia avoid having an influence when the Caspian Sea is becoming an increasingly important strategic route for both Russia and Iran?
Many have repeatedly noted that Iran's behaviour resembles that of the Soviet Union shortly before its collapse: socioeconomic problems, internal political disagreements and, finally, a logic behind foreign-policy actions that is not always clear.
The difference is that, unlike the late Soviet Union, Iran still has a strong supreme authority. At least, Iran goes to great lengths to demonstrate this. Any dissent is suppressed firmly and conspicuously. But there is a difference between being uncompromising and principled with enemies and taking the same approach with neighbours and, essentially, friendly countries.
Moreover, is it really worth fighting so hard for 20% of the Caspian when the sea has become roughly 8% shallower over the past 30 years? The decline is particularly noticeable in the Russian and Kazakh sectors. In some areas, the water has receded dozens of kilometres from the shoreline. At this rate, countries that controlled relatively large shares of the water surface will, in practice, see their proportion shrink.
Conversely, Iran's 13% could theoretically turn into the coveted 20%. So is it really worth breaking lances over the issue?
Yes, the conservative wing of Iran's leadership feels it is in a strong position on the back of its victory over the United States, which apparently explains its maximalist demands regarding Hormuz and the lifting of sanctions. These victorious sentiments appear to be spilling over into the entire perimeter of foreign policy, including the Caspian issue. The thinking seems to be: there it is, divine providence. Iran remained firm in its position and did not retreat, so the higher powers saw it, rewarded it, and the country must remain equally firm and consistent from now on.
