DUBAI (REUTERS) - World powers negotiating with Teheran over its disputed nuclear programme must come up with new proposals before talks in Geneva on Oct 15-16, Iran's foreign minister said.

The United States wants Iran to respond to proposals by world powers in February as a starting point for talks. If the parties cannot agree on how to start the negotiations, it casts doubt on whether a resolution can be agreed within the six months in which Iranian President Hassan Rouhani says he wants a deal.

Britain, China, France, Russia and the US - the five permanent members of the United Nations Security Council - plus Germany, the so-called P5+1, said in February they want Iran to stop enrichment of uranium to 20 per cent, ship out some stockpiles and shutter a facility where such enrichment is done.

In return, they offered relaxation of international sanctions on Iran's petrochemicals and trade in gold and other precious metals.

US officials said last week Secretary of State John Kerry had secured an agreement from his Chinese counterpart calling for Iran to respond positively to existing nuclear proposals by the six powers.

"The previous P5+1 plan given to Iran belongs to history and they must enter talks with a new point of view," Foreign Minister Mohammad Javad Zarif said in an interview with Iranian state television late on Saturday. "The players must put away this illusion that they can impose anything on the Iranian people."

The election of Mr Rouhani in June and his appointment of US-educated Zarif as foreign minister and chief nuclear negotiator have raised hopes for a solution to the decade-old dispute over Iran's nuclear programme. Western powers believe Iranian enrichment activities are aimed at achieving nuclear weapons capability, whereas Iran insists its programme is purely for civilian purposes - generating electricity and for a medical research reactor. Each side wants the other to make the first move.

"There is a new tone (in Iran). We want it to be sincere, but we need to see deeds," French Foreign Minister Laurent Fabius told Europe 1 radio on Sunday.

But, he said, there was limited time to resolve the dispute while maintaining the Western goal of ensuring Iran is not able to make nuclear arms. That was because the heavy water reactor in Arak, in western Iran would be able to produce plutonium.

"If it were completed, we wouldn't be able to destroy it because if you bomb plutonium it will leak. This means it's a race against time," he said.