A foreign ministerial meeting of Caspian Sea states was held in Astana, Kazakhstan, on Wednesday to work out the details of a draft convention on the legal status of the sea and the agenda for the upcoming Fifth Caspian Summit.
The summit of heads of state will also be hosted by Kazakhstan.
Foreign Minister Mohammad Javad Zarif arrived in the Kazakh capital on Tuesday at the head of a delegation of legal and political experts, Fars News Agency reported.
Iran, Russia, Kazakhstan, Azerbaijan and Turkmenistan are littoral states of the resource-rich Caspian Sea, which have been in talks since 1991 to create a legal regime to determine their territorial rights.
As yet, such negotiations have not produced the desired results.
The last presidential summit took place in the Russian port city of Astrakhan in 2014, during which the five signed an agreement to promote the sustainable use of the Caspian Sea and protect its marine life.
They also agreed on key principles of their activity in the Caspian Sea, set out in a political declaration that would form the convention's cornerstone.
All parties were committed to improving the habitats of sturgeons in the sea, developing natural and artificial reproduction of fish resources and curbing illegal fishing.
Caspian Sea is the largest enclosed body of water by area and variously classed as the world's largest lake or a full-fledged sea.
The issue of Caspian Sea's legal regime gained importance, following the breakup of the Soviet Union and the emergence of new independent states.
The Iranian foreign minister addressed the ministerial conference and met a number of his counterparts, including the host's foreign minister, Erlan Idrissov, on the sidelines of the event.
