VIENNA (AFP) - The United Nations atomic watchdog said on Friday that its chief has accepted an invitation to visit Iran, raising hopes for a long-stalled probe into Teheran's suspected bomb-making efforts as tough talks continued in Geneva.

International Atomic Energy Agency director general Yukiya Amano "will travel to Teheran on Nov 10 to meet senior Iranian leaders on Monday, Nov 11, with the aim of strengthening dialogue and cooperation," it said.

"Separately, as previously announced, IAEA and Iranian experts will meet in Teheran on Monday to discuss technical issues," the Vienna-based body said in a statement.

The announcement of Mr Amano's first visit since May 2012 came as six world powers held a second day of negotiations with Iran in Geneva on easing the long-running standoff over the Islamic republic's nuclear programme.

The IAEA conducts regular inspections of Iran's nuclear facilities but it also wants to investigate possible efforts before 2003, and maybe since, to develop a nuclear weapon.

Iran's separate talks with the United States, China, Russia, Britain, France and Germany, known as the P5+1, are focused more on Teheran's current activities, in particular uranium enrichment.

Iran rejects the IAEA's weaponisation claims, and says that they are based on faulty intelligence from the likes of the Central Intelligence Agency and Israel's Mossad that it complains it has not even been allowed to see.

Tehran has so far resisted IAEA requests to visit sites where these alleged activities took place as well as to consult documents and speak to Iranian scientists.

For two years, since the IAEA published a major report on these allegations in November 2011, talks between Iran and the agency failed, including during Amano's high-profile visit 18 months ago.

But since taking office in August, Iranian President Hassan Rouhani has set a new tone, and two meetings in Vienna on Sept 27 with the IAEA and Oct 28 were hailed by both sides as constructive.

"The only reason he (Amano) would go would be if he's confident that they were going to agree on something," a second Western diplomat told AFP on condition of anonymity.

He added that he expected "some sort of first round of confidence-building measures to get the ball rolling."

Last week Iran presented to the IAEA a new proposal on solving the dispute, but like a new offer made by Iran to the six P5+1 powers in Geneva on Oct 15-16, details have been kept secret.

Iran and the IAEA had already been due to hold talks in Tehran on Monday, but it had not been announced that Amano would be present. Iran revealed its invitation to him on Tuesday.

The sites include the Parchin military base where the IAEA wants to probe claims that scientists conducted explosives tests that it says would be "strong indicators of possible nuclear weapon development".

Western countries have accused Iran of bulldozing evidence at Parchin, and Amano said in June that heavy construction work spotted by satellites meant "it may no longer be possible to find anything even if we have access".

Improved relations between Iran and the IAEA are also important because the P5+1 want Teheran to submit to more intrusive inspections by the watchdog as part of a wider accord on ending the standoff.

This would ease fears of an Iranian "break out" - that the Islamic republic could produce enough highly-enriched uranium for a nuclear weapon before the IAEA can detect it.