Iran has invited the UN atomic watchdog to visit the country, but it is unclear whether inspectors would have access to sites where covert nuclear weapons activity is suspected, Western diplomats said Tuesday.
"Our understanding from our conversations with the IAEA is that... Iran has made a sort of general invitation, but there is nothing specific in there," one diplomat to the Vienna-based agency told AFP on condition of anonymity.
"We don't know how the agency is going to reply yet. To us it seems in keeping with Iran trying to mollify the IAEA without really offering anything substantive."
A second diplomat said it was unclear whether the Iranian letter dated December 14 addressed any of the issues raised in November's hard-hitting report from the International Atomic Energy Agency.
"I doubt the letter contains any offer of engagement" on such issues, the diplomat told AFP. "I am very sceptical on that."
The IAEA published a report on November 8 expressing "serious concerns" that the Islamic republic "has carried out activities relevant to the development of a nuclear explosive device".
Iran, already subject to four rounds of UN Security Council sanctions, rejected the report as "baseless".
The United States welcomed the fact that the IAEA had been invited back, but State Department spokeswoman Victoria Nuland added: "We want to make sure that this visit is complete."
She said the inspectors should be able to "get to all the sites they want to get to; that they can interview anybody that they want to see; and that they get to all the records that they need to see, because this is the standard that we want to see Iran implement."
Ten days after the report was published the IAEA board passed a resolution submitted by all five UN Security Council permanent members condemning Iran but stopping short of reporting it to New York or setting a deadline for Tehran to comply.
Iran's ambassador to the IAEA, Ali Asghar Soltanieh, angrily called the move "unprofessional, unbalanced, illegal and politicised" and said it put future cooperation with the agency in doubt.
Soltanieh was not immediately available for comment.