The United States urged Iran at a U.N. nuclear agency meeting on Thursday to implement nuclear transparency measures outlined in a preliminary deal it reached with six world powers in April.

Laura Kennedy, the U.S. ambassador to the International Atomic Energy Agency in Vienna, told a session of the IAEA's 35-nation governing board that it "remains critical for Iran to implement the provisions of Modified Code 3.1 ... without delay". This provision requires from Iran early notification of the construction of any new nuclear facilities.

Kennedy also said it was important for Iran to implement the IAEA's Additional Protocol, which allows U.N. inspectors under specific circumstances to visit Iranian sites with as little notice as two hours' notice.

The Additional Protocol also allows the agency to collect environment samples, such as soil, which can yield information on nuclear activities years after they have taken place.

Kennedy also said Iran had still not resolved longstanding IAEA questions about the "possible military dimensions" (PMD), mainly before 2003, of its nuclear programme.

Iran and the six powers reached a framework nuclear deal on April 2 in Switzerland and are seeking to strike a final agreement by June 30 under which Iran would restrain its nuclear programme in exchange for relief from economic sanctions.

By Reuters