Aras–Atrak agreement establishes shared water rights

A CIA–MI6-backed coup overthrew Mohammad Mossadegh. The ensuing suppression of Tudeh narrowed the Soviet-linked left’s political space and strengthened the Shah’s Western orientation.

Iran and the USSR signed a settlement of border disputes and mutual financial claims from World War II, creating a legal basis for more predictable relations.

Iran deposited its accession instruments for the Baghdad Pact. Western security alignment increased tension with Moscow, which opposed Iran’s participation.

Mohammad Reza Shah and Queen Soraya arrived in Moscow for a state visit, showing that Western alignment still allowed direct diplomacy with the Soviet leadership.

Iran and the USSR signed a treaty on their frontier regime and procedures for investigating and settling border disputes and incidents.

Soviet–Iranian non-aggression talks ended without agreement amid disagreement over Iran’s Baghdad Pact membership and its planned defense agreement with the United States.

Iran signed a cooperation agreement with the United States at Ankara, reinforcing its Western security ties after the failure of Soviet–Iranian talks.

Iran assured the USSR that it would not permit foreign missile bases on Iranian territory or allow Iran to be used for aggression against the Soviet Union.

Iran and the USSR concluded an economic and technical cooperation agreement underpinning the Aras hydro-engineering complex and Mil-Mugan diversion dam.

Iran and the USSR signed a payments agreement, adding a financial instrument to their growing economic relationship.