Iran agreed a timetable with the International Atomic Energy Agency (IAEA) last month to answer outstanding questions over its atomic drive, in a move that is expected to stave off the threat of sanctions for several months.

"We will continue our cooperation with the IAEA," foreign ministry spokesman Mohammad Ali Hosseini told reporters.

"But if there is a new United Nations (Security Council) resolution we will reconsider our cooperation with the IAEA and we will study different options."

Hosseini did not specify what the options were but top nuclear negotiator Ali Larijani has already warned that any further sanctions will render Iran's cooperation with the agency "sterile".

The IAEA has welcomed Iran's willingness to answer the questions on its atomic drive as a "a significant step forward" but the United States has expressed doubts over the agreement.

The United States accuses Iran of seeking to manufacture nuclear weapons but Tehran insists its atomic drive is aimed only at generating electricity for a growing population.