The United Nations headquarters building is pictured though a window with the UN logo in the foreground in the Manhattan borough of New York, Aug. 15, 2014. Photo: REUTERS/Carlo Allegri

Tehran called on the United Nations to intervene in what it called the “tightening of restrictions on Iran‘s diplomatic mission to the United Nations in New York,” according to a foreign ministry statement published on Thursday.

The statement also condemned a decision by the US State Department “to prevent the continuation of the activities” of three employees of Iran‘s mission in New York.

The statement did not specify when the restrictions had been tightened, but in September, the United States imposed strict limits on the Iranian delegation attending the UN General Assembly in New York, curbing their movement and banning access to wholesale stores and luxury goods.

“The imposition of extensive restrictions on the residence and movement of Iranian diplomats, tightening restrictions on bank accounts, and imposing restrictions on daily purchases are among the pressures and harassment … to disrupt the normal and legal duties of Iranian diplomats,” the statement said.

Prior to the September restrictions, Iranian delegation members were allowed to travel between the United Nations, the Iranian UN mission, the Iranian UN ambassador’s residence, and John F. Kennedy International Airport.

Tensions between Tehran and Washington heightened after the two countries engaged in five rounds of indirect nuclear negotiations that ended with a 12-day air war in June in which Israel and the US bombed Iranian nuclear sites.