The UN atomic watchdog said it needs 1 million euros in extra funding to help pay for its monitoring of a four-month extension of an interim nuclear deal between Iran and six world powers, Reuters reports.

The request was made in a note to member states of the UN International Atomic Energy Agency (IAEA) dated July 24, according to Reuters, six days after the extension of last year's agreement was announced.

Iran and the six powers - the United States, France, Germany, Russia, Britain and China - agreed to continue talking after they failed to meet a July 20 deadline for a final accord to end the decade-old dispute over Iran's nuclear program.

The IAEA has a pivotal role in verifying that Iran is complying with the preliminary agreement, under which Tehran halted its most sensitive uranium enrichment in exchange for a limited easing of sanctions that are hurting its economy.

The short-term deal was designed to buy time for talks on a comprehensive agreement on the permissible scope of a nuclear program which Iran says is peaceful but which the West fears may be aimed at developing an atomic weapons capability.

The IAEA saw its workload increase significantly under last November's preliminary accord, initially due to run for six months from Jan 20 but now prolonged until Nov 24.

Its inspectors accessed Iran's uranium enrichment facilities of Natanz and Fordow daily, compared to about once a week before. The agency also provides monthly updates to member states on how Iran is implementing its commitments.

IAEA Director General Yukiya Amano said in January the agency would nearly double the number of people it has working on Iran as a result of the November agreement. He then asked for about 5.5 million euros in extra voluntary contributions, money which diplomats later said it had obtained without problems in view of the deal's political importance.

In the new note, the IAEA said it had received a request from the seven countries involved in the negotiations to "continue to undertake the necessary nuclear-related monitoring and verification activities in Iran" under the accord. That would include monitoring of additional measures to be taken by Iran as part of the terms of the extension, such as Iran's commitment to turn some of its higher-grade enriched uranium oxide into nuclear fuel for a Tehran research reactor.

"Continuation of the ... activities will require additional financial resources for the Agency," the note said.

"Assuming that all contributing Member States agree to the continued use of their unspent contributions, an additional amount of 1 million euros would be required," it said.