Officials from the United States, Britain, China, France, Russia and Germany are due to meet later this month in a bid to renew their efforts to make Iran halt its sensitive nuclear work, the State Department said on Monday.
"I can only narrow it down to mid-April. We're going to wait, we're going to let our hosts announce the meeting," State Department spokesman Sean McCormack said.
The spokesman did not offer more details of the meeting, including who will host the talks.
Daniel Fried, acting undersecretary of state for political affairs, is to attend the scheduled talks, according to the spokesman.
Pushed by the United States, three UN Security Council resolutions have been passed to punish Tehran for its insistence to hold on its civilian nuclear program.
Washington has accused Iran of trying to develop nuclear weapons under the cover of a civilian nuclear program. Iran has denied the U.S. charges and insisted that its nuclear program is for peaceful purposes only.