The European Union asked Iran to cooperate with the UN atomic agency's probe into its past nuclear activities if Tehran wants a nuclear deal with the major powers that will see removal of sanctions.
The EU statement comes ahead of a June 30 target date for such an agreement. It was obtained by The Associated Press ahead of its delivery at a meeting of the International Atomic Energy Agency that opened Monday.
Iran denies the allegation that it may have been seeking to develop a nuclear weapons capability under the guise of a civilian program, saying the work is only for peaceful purposes such as generating electricity. However, Iran increased its cooperation with the UN nuclear watchdog's investigation into what its calls possible military dimensions of Tehran's nuclear program after President Hassan Rouhani took office in August 2013 to help end the 12-year nuclear dispute and secure the lifting of "cruel" sanctions.
The EU statement said getting to the bottom of the allegation "will be essential" to a nuclear deal.
Iran would accept temporary limits on its present nuclear activities under any long-term settlement.
Meanwhile, the IAEA director said on Monday any possible military dimensions of Iran's nuclear program can be clarified if the details of a preliminary agreement reached in April between Tehran and the major powers in the Swiss city of Lausanne are implemented, Reuters reported.
"I am confident that the clarification of issues with possible military dimensions is possible within a reasonable timeframe if Iran implements the measures envisaged in the Lausanne announcement," Yukiya Amano said. It is the first time Amano has clearly linked the technical UN investigation to the political talks Iran is holding with the United States, France, Britain, China, Russia and Germany. As part of the initial deal, Iran would implement the so-called Additional Protocol giving the IAEA expanded rights of access to information and sites.
"Implementation by Iran of the Additional Protocol will ... significantly increase the agency's ability to provide credible assurance about the absence of undeclared nuclear material and activities in (Iran)," Amano said.