A team of U.S. nuclear negotiators is scheduled to meet with Iranian officials on December 15 and 16 in Geneva, Switzerland for talks that conclude a day before Iranian negotiators meet there with six world powers on December 17.
The U.S. negotiating team at the bilateral talks is to be led by Under Secretary of State for Political Affairs Wendy Sherman.
Helga Schmid, deputy secretary general for the European Union's External Action Service, will attend some of the bilateral talks
In November, Iran and the so-called P5+1 group failed to reach a permanent agreement before a self-imposed deadline but decided to extend their nuclear talks until July 1, 2015.
The P5+1 is comprised of the United States, Britain, France, Russia, and China plus Germany.
Western powers want a deal that ensures Iran can't secretly build nuclear weapons.
Iran says its nuclear program is only for peaceful civilian purposes.