Officials from six countries trying to address concerns about Iran's nuclear program will meet in Germany this week, a government spokesman said Monday.

Foreign Ministry spokesman Jens Ploetner said the meeting at "high civil servant level" will be held in Germany, but not in Berlin. He did not give more details about its location or timing.

French Foreign Ministry spokesman Eric Chevallier said the meeting would be in Frankfurt to prepare for a September meeting on the Iran nuclear issue, which will take place on the sidelines of the United Nations General Assembly in New York.

The five permanent members of the U.N. Security Council — the U.S., Britain, France, Russia and China — and Germany have held regular meetings on Iran.

Iran insists its nuclear program is peaceful and geared solely toward generating electricity. The U.S. and important allies contend it is covertly trying to build an atomic weapon and have raised the prospect of further sanctions.

Last week, German Chancellor Angela Merkel urged Tehran to stop its nuclear program and return to negotiations by the September meeting, or risk facing stiffer sanctions "in the energy, financial and other important sectors."