TEHRAN, Iran — Tehran and Moscow have agreed to expand the number of countries participating in the plan to enrich Iranian uranium in Russia, Iran's foreign minister said Saturday, describing a compromise that could satisfy U.S. concerns about the nuclear program.

Foreign Minister Manouchehr Mottaki refused to say which other countries would be included. However, a top Iranian nuclear official was just in Beijing to discuss the Russian plan, which is designed to ensure that Tehran does not attempt to produce fuel for nuclear weapons.

"Increasing the number of partners in the plan was agreed," Mottaki told a news conference. "The place or the places ... is under review while negotiations continue."

Under the plan, Iran would ship its uranium to Russia, where it would be enriched and then returned to Iran for use in its nuclear reactor. That would, in theory, satisfy the world that Iran was using the process only to produce fuel for nuclear reactors to generate electricity.

Tehran claims its nuclear program is for civilian purposes, but the United States and Europe fear the Iranians are using the program as a cover to make nuclear weapons.

Uranium that is sufficiently enriched can produce materials for bombs.

The United States is pressing for the International Atomic Energy Agency to refer Iran to the UN Security Council for alleged violations of an international nuclear arms control treaty. The council has the power to impose economic and political sanctions on Iran.

The IAEA will consider the issue at a Thursday meeting in Vienna, Austria.

Mottaki also said Iran needs more time to negotiate with Europe. After Iran broke IAEA seals on its uranium enrichment facility at Natanz earlier this month, Britain, France and Germany — who were negotiating with Iran — said further talks were pointless.

Iran contends it is within its rights to control the full nuclear fuel cycle from mining uranium to enriching it for nuclear power generation.

"Discussions with Europeans in their capitals and in Vienna were continuing, and we hope they reach a satisfactory conclusion," Mottaki said. "I think there is need for more time to continue the negotiations — until March."

It was not clear if he meant to signal that a fresh official round of talks was planned.

At the World Economic Forum in Davos, Switzerland, British officials said they would meet Monday with the deputy of Iran's top nuclear negotiator Ali Larijani.

"The problem is one of Iran's own making," Foreign Secretary Jack Straw said at the forum.

"What we have said is they have to provide objective guarantees that their nuclear capability is solely for civil nuclear power purposes. ... What we want to see is them coming forward and then we can get to a normalization, plenty of incentives and all the rest."

Former President Clinton said all options for Iran must be considered, including UN sanctions.