At a meeting with Iran's nuclear negotiator in Geneva on July 19, the UN Security Council's five permanent members plus Germany set Tehran an informal two-week deadline to show it is ready to suspend uranium enrichment in return for a reprieve from new UN sanctions.
"We are offering Iran comprehensive cooperation," German news magazine Der Spiegel quoted German Foreign Minister Frank-Walter Steinmeier saying in an interview released on Saturday, Aug 2.
"I appeal again to the Iranian side no longer to play for time, but to give us a usable answer to our offers and stop dallying."
However Iranian President Mahmoud Ahmadinejad on Saturday said his country would not retreat "one iota" from its nuclear rights, news agency Reuters reported.
Iran refuses to play along
Western countries have slapped several sets of sanctions on Tehran over its refusal to halt uranium enrichment which the West suspects is being used to develop nuclear weapons.
Iran vehemently denies seeking nuclear weapons, insisting that its program is designed to provide energy for its growing population for the time when its reserves of fossil fuels run out.
At the Geneva meeting in July, the six western powers put forward an enhanced offer of financial and diplomatic incentives. It includes far-reaching economic cooperation with Iran, including in the field of civilian-sector nuclear power, in return for a pledge by Tehran to refrain from uranium enrichment activities.
Britain, France, Germany, the United States, Russia and China are offering Iran a "freeze for freeze" approach. In a pre-negotiation phase, Tehran would not expand its enrichment facility in Natanz, while the six nations would not press for additional Security Council sanctions.
After confidence between the two sides has been established in this phase, Iran would halt its uranium enrichment, and comprehensive talks about the world powers' offer of cooperation and similar package put forward by Iran could start.
But Iran's top nuclear negotiator Saeed Jalili said after talks in Geneva that in any next round of talks Iran was not ready to discuss a freeze in enrichment proposed by the "sextet" in return for the UN Security Council halting further sanctions measures.
"Real commitment to diplomatic solution"
The meeting in Geneva took on added importance with the US sending a high-ranking representative, Undersecretary of State William Burns -- the first US diplomat in 30 years to participate in negotiations with Iran.
"Even the Americans have visibly got involved and sent a negotiator for the first time," Steinmeier told Der Spiegel. "It is all meant to demonstrate there really is a commitment to a diplomatic solution."
Steinmeier said he expected a clear signal in favor of a mutual suspension.
"We would then suspend our efforts for sanctions and Iran would suspend the expansion of its centrifuges. It's a clear offer that deserves a clear answer, and a prompt one."
The minister said it would be "negligent" not to use the opportunity.
In Brussels, meanwhile, EU diplomats said Saturday that the EU was still awaiting Tehran's official response to an offer of new talks to resolve the dispute over Iran's nuclear activities, and that an answer may be coming on Monday.