Iran agreed to host a high-level team of United Nation’s nuclear inspectors later this month, Western diplomats said, a surprise development that could help to curb building tensions with the West…

Unclear, said the diplomats, was whether Tehran would let the inspectors visit key nuclear sites and interview the Iranian official the U.S. and the U.N. agency believe may head a nuclear-weapons program…

U.S. and European officials on Thursday said they were skeptical of any renewed outreach by Tehran. They said they were concerned Iran could try to use a diplomatic outreach to divide the international community and diminish support for new financial measures against Iran.

In December, Catherine Ashton of Britain, who heads the international group of nations seeking to negotiate with Iran on the nuclear issue, sent a formal letter to Tehran seeking new talks. But U.S. and European officials said Thursday that Iran’s chief nuclear negotiator, Saeed Jalili, never responded.