MOSCOW (REUTERS) - Russia is hopeful that talks between Iran and world powers will produce a preliminary deal this week to ease the standoff over Tehran's nuclear programme, Foreign Minister Sergei Lavrov said on Wednesday.

Iranian negotiators and diplomats from the United States, Russia, China, France, Britain and Germany were due to meet in Geneva on Wednesday to discuss a proposed deal under which Tehran would suspend parts of its programme in exchange for some sanctions relief.

"We hope the efforts that are being made will be crowned with success at the meeting that opens today in Geneva," Mr Lavrov told a joint news conference after talks with Brazilian Foreign Minister Luiz Alberto Figueiredo.

Mr Lavrov said in remarks broadcast on Saturday that chances of reaching an agreement were very good and the opportunity should not be passed up.

He has also suggested Iran is prepared to produce less enriched uranium and halt production of uranium enriched to a fissile concentration of 20 per cent, a relatively short step from weapons-grade material. Those are two of the steps Western powers want Iran to take.

Russia, which built Iran's first nuclear power plant and has much warmer ties with Tehran than the United States does, has expressed less suspicion than Western powers that Iran may be seeking to develop nuclear weapons capability. Iran says its nuclear programme is for peaceful purposes only.