PARIS - As it prepares for two sets of negotiations on its disputed nuclear program, Iran said Tuesday that it was converting some of its enriched uranium into reactor fuel, the state news agency IRNA reported, potentially limiting the expansion of stockpiles that the West fears could be used for weapons.

Iranian officials are to meet Wednesday in Tehran with Herman Nackaerts, the deputy director of the International Atomic Energy Agency, the U.N. nuclear watchdog, who has been pressing for access to a restricted military area at Parchin, 20 miles south of Tehran. International inspectors suspect the site may have been used for testing bomb triggers.

Later this month, Iranian negotiators are to meet in Kazakhstan with representatives of six powers -- the United States, China, Russia, Britain, France and Germany -- for another round in a series of long-running and inconclusive talks about curbing Tehran's nuclear enrichment program.

Western countries suspect Iran is seeking to acquire the technology to make nuclear weapons, but Iran says the program is for peaceful purposes.

At a news conference Tuesday in Tehran, Ramin Mehmanparast, the Foreign Ministry spokesman, was asked to comment on a news report that Iranian scientists had converted some uranium enriched to 20 percent purity into fuel for a research reactor in Tehran. The spokesman said the "work is being done" and details had been sent to the IAEA.

Iran's stockpile of enriched uranium is believed by international inspectors to be of far lower purity than is required to make nuclear weapons.