A Russian delegation arrived in Tehran on Monday for a visit that includes a meeting with Iranian President Masoud Pezeshkian as Tehran and Moscow prepare to sign a comprehensive cooperation agreement.

The Russian delegation is headed by deputy prime ministers Alexei Overchuk and Vitaly Savelev, Russia's Interfax news agency said, adding, “The parties are expected to discuss the joint work of Iran and the countries of the Eurasian Economic Union (EAEU) within the framework of a full-fledged agreement on a free trade zone.”

Iran's Foreign Ministry Spokesperson Esmail Baghaei also said Monday that Iran and Russia have been working on setting a date to complete an agreement, which has been announced a few years ago. He said the deal is set to be finalized in January.

Tehran and Moscow initially signed a long-term agreement in March 2001. Officially known as the Treaty of the Foundation of Mutual Relations and the Principles of Cooperation between the Islamic Republic of Iran and the Russian Federation Act, it was initially set for ten years but was extended twice for five-year terms.

According to Iran’s ambassador to Russia, the countries agreed to extend the agreement for another five years in 2021, setting its expiration date in 2026.

In 2023, reports of possible difficulties in developing the new agreement with Russia. Very few details have emerged on what the new agreement would include.

Russia has bolstered closer ties with Iran and other countries hostile towards the United States, such as North Korea, since the start of the Ukraine war.

Russian Foreign Minister Sergei Lavrov said in October that Moscow and Tehran intended to sign a deal which would include closer defense cooperation.

The United States accused Tehran in September of delivering close-range ballistic missiles to Russia for use against Ukraine, and imposed sanctions on ships and companies it said were involved in delivering Iranian weapons. Tehran denies providing Moscow with the missiles.