TOKYO (AFP) - Japan's foreign minister will go to Iran next month, he said on Tuesday, in the latest sign of Teheran's rapidly thawing relationship with the Western world.

Fumio Kishida said he plans a three day trip from November 9, the day after Iranian negotiators wrap up talks with world powers in Geneva over the country's nuclear programme.

Western nations, led by the United States, have long suspected that Iran is trying to build an atomic bomb, but Teheran denies this, saying its nuclear programme is peaceful.

It has endured years of sanctions and defied multiple UN Security Council resolutions under hardline leaders.

But since President Hassan Rouhani, who is seen as a relative moderate, took office in August hopes have been raised of an end to the long-running crisis, especially after a round of hectic diplomacy during the UN General Assembly in September.

That set up a series of meetings, including that in Geneva next month of the so-called P5+1 of the United States, Britain, France, China and Russia plus Germany, with hopes high of a breakthrough.

Tokyo hopes to play a role in asking Teheran to "show flexibility", taking advantage of its longstanding friendly ties with Iran, a foreign ministry official said, noting that Japan is one of a small number of wealthy countries that has an embassy there.

Resource-poor Japan is heavily dependent on the Middle East and has maintained relations with Iran in the face of pressure to ostracise the country, although its oil imports from Iran last year dropped 40 percent in a nod to international sanctions.

Kishida, whose constituency is located in Hiroshima, one of two Japanese cities that were devastated by US atomic bombings towards the end of World War II, "has strong interest in the nuclear issue", the official said.

The foreign minister is expected to head to India after Teheran.