| VIENNA/ST GALLEN, Switzerland
VIENNA/ST GALLEN, Switzerland The five permanent members of the U.N. Security Council put pressure on Iran on Thursday to allay international concern about its nuclear program, and said they expected talks with Tehran to lead to concrete steps toward a negotiated solution.
Iran and major powers resumed talks in mid-April in Istanbul after a gap of more than a year - a chance to ease escalating tension and help to avert the threat of a new Middle East war. They are to meet again on May 23 in Baghdad.
In a joint statement issued at a nuclear non-proliferation conference in Vienna, the United States, France, Russia, China and Britain pressed Tehran to agree urgently with the U.N. nuclear watchdog on access to "relevant sites and information".
"We remain concerned by Iran's persistent failure to comply with its obligations under UNSC (U.N. Security Council) resolutions," the statement said, referring to repeated demands that Tehran curb its disputed nuclear program.
The West says Iran's nuclear work is a cover for developing atomic bombs and wants verifiable assurances to the contrary from Tehran - for example, by accepting much more intrusive U.N. nuclear inspections and limiting its enrichment capacity.
Iran denies having a weapons agenda, saying it is enriching uranium solely for peaceful energy purposes.
Iranian Vice President Mohammad Reza Rahimi said he hoped for "constructive steps" during the talks in the Iraqi capital.
The West should "abandon weak allegations that raise the tension in the region," he said during a visit to Beirut.
The week before the broader political negotiations take place in Baghdad, the U.N. nuclear agency and Iran will hold a new round of discussions on May 14-15 in Vienna after two meetings earlier this year failed to make any headway.
The International Atomic Energy Agency (IAEA) wants Iran to address questions raised in a report it issued last November detailing what it said were suspected Iranian research and development activities relevant to making nuclear weapons.
Iran has dismissed the allegations as fabricated.
Western diplomats say Iran appears to be stonewalling an IAEA request for access to a military site, Parchin, where it believes military-related nuclear research may have taken place.
The diplomats say they suspect Iran may be "sanitizing" the site southeast of Tehran of any incriminating evidence before U.N. inspectors can visit, a suspicion Tehran dismisses.
IAEA Director General Yukiya Amano told Reuters that his inspectors wanted to go to Parchin "rather sooner than later" and reiterated that the U.N. agency had recently noticed what he referred to as some "activities" there.
"We would also like to have access to, not only the site, but information and people related to Parchin," Amano said on the sidelines of a symposium in the Swiss town of St. Gallen.
"I hope that these activities will not make our verification difficult."
He did not elaborate but his choice of words has been interpreted by Western diplomats as an indication that the agency also thought Iran might be cleaning up the site.
"We hope we can make progress," Amano said. But asked whether he had any indication that the requested access would now be granted by Iran, Amano said: "I do not have a concrete indication that we would have access to Parchin."
Thursday's statement by the five powers - which together with Germany are involved in nuclear talks with Iran - said they were seeking a "sustained process of serious dialogue", where both sides can take urgent action to build confidence.
Last month's discussions in Istanbul were "constructive and useful," the statement said.
"We expect that subsequent meetings ... will lead to concrete steps toward a comprehensive negotiated solution which restores international confidence in the exclusively peaceful nature of the Iranian nuclear program," it added.
Western states have imposed expanded, more biting sanctions against Iran's energy and banking sectors since the beginning of this year. The European Union is preparing to slap a total embargo on the purchase of Iranian crude oil in July.
Iran said this week it would seek an end to sanctions over its nuclear activities at the Baghdad talks, reflecting a hardening public line in the Islamic Republic that an end to sanctions is vital to the success of the negotiations.
However, the United States and its allies have made clear Tehran must take action to allay their concerns about its nuclear ambitions before they can consider relaxing sanctions.
(Additional reporting by Oliver Holmes in Beirut, Editing by Diana Abdallah)