NEW YORK (Reuters) - Boeing signed an agreement to sell planes to Iran Air, the company said on Tuesday (June 21), confirming Iranian statements about the historic deal to sell 100 jetliners to the airline.

The tentative agreement, which marks Boeing's first sale to Iran since its Islamic Revolution in 1979, resulted from the nuclear accord reached with the country last year.

The agreement brings more work to Boeing's factories in Washington state and South Carolina, and helps the aerospace and defence company catch up with a US$27 billion (S$36.3 billion), 118-plane order Iran placed with Airbus in January.

Boeing said in a statement that it had signed a memorandum of understanding with state carrier Iran Air "expressing the airline's intent to purchase Boeing commercial passenger airplanes".

The Chicago-based company declined to discuss the number or type of planes it would sell, or the timetable for delivery of the aircraft. But the head of Iran's Civil Aviation Organisation, Ali Abedzadeh, told the state-run daily newspaper Iran on Friday that the signed deal was for 100 Boeing aircraft.

Such an order would be worth about US$11 billion at list prices if Iran Air bought only Boeing 737 single-aisle jetliners, and perhaps twice that much if it included a significant number of twin-aisle planes such as the 777 or 787 Dreamliner.

A large order was expected, but the sale raised concerns among some Congress members, who feared it could threaten US national security.

Boeing's statement said the talks that led to the memorandum of understanding were conducted "under authorisations from the US government following a determination that Iran had met its obligations under the nuclear accord reached last summer".

Boeing said it would "continue to follow the lead of the US government with regards to working with Iran's airlines". It added that "any and all contracts with Iran's airlines will be contingent upon US government approval".