Iran opened the door Sunday for U.S. help in building a nuclear power plant — a move designed to ease American suspicions that Tehran is using its nuclear program as a cover to build atomic weapons.

The offer, which did not seem likely to win acceptance in Washington, was issued as Israel said it had not ruled out a military strike against Iranian nuclear facilities.

"America can take part in international bidding for the construction of Iran's nuclear power plant if they observe the basic standards and quality," Foreign Ministry spokesman Hamid Reza Asefi said in a news conference.

Asefi was apparently talking about a 360-megawatt light water nuclear power plant that the head of the country's atomic organization said Saturday would be built in southwestern Iran.

Iran also wants to produce 2,000 megawatts of electricity by building nuclear power plants with foreign help in southern Iran.

In Washington, neither the State Department nor the White House issued any comment on the proposal.

While it was unclear how the Americans would react to the Iranian proposal, relations between Tehran and Washington, which were severed after Iran's 1979 Islamic revolution, have seldom been worse. The United States has imposed unilateral sanctions on Iran, preventing American companies from doing business in Iran.

The United States also has ratcheted up pressure against Iran, accusing it of pursuing a nuclear weapons program and supporting anti-Israeli militants. Iran says its nuclear program is designed only to generate electricity.

Still, the United States is pushing for Tehran to be hauled before the U.N. Security Council, where it could face economic sanctions for violating a nuclear arms control treaty.

The Iranian offer comes at a time when Iran is facing a barrage of criticism over President Mahmoud Ahmadinejad's recent remarks, first that Israel should be wiped off the map and later that the Jewish state should be moved to Europe.

On Sunday, Israel denied a British newspaper report it has plans to attack Iran in March, but officials said they would not rule out a military strike if Iran makes advances in building nuclear weapons. The report appeared in the Sunday Times.

Amos Gilad, a senior Defense Ministry official, said attention was now focused on an international solution over the Iranian program but added, "It isn't correct to say that a country that is threatened should deny that it will ever consider a different option."

Israel Foreign Minister Silvan Shalom said the country would never accept a nuclear-armed Iran.

"Israel can't live in a situation in which Iran has the atomic bomb," he said.

Iranian political analyst Saeed Leilaz said Tehran's offer was somewhat genuine but also politically motivated.

"Iran made the offer seriously to show the United States that it won't produce a bomb and ease its concern," Leilaz said. "And partly, Iran made the offer because it's almost sure the United States won't accept it."

Iran has been involved in stalled talks with European negotiators aimed at making Tehran permanently freeze nuclear enrichment, which can produce material for use in warheads or fuel for nuclear plants to generate electricity.

Tehran temporarily froze its enrichment program in November 2004, but the Europeans want it permanently halted.

The United States backs the Iran-Europe talks, which broke off in August but will resume Dec. 21 in Vienna, Austria. Tehran since has restarted uranium conversion, a precursor to enrichment.

"The (Vienna) meeting will be a serious one," Asefi said. "Everything is dependent on the meeting and the talks. Everything will be decided there. We will make a decision based on its results in the future."

Asefi refused to speculate on the result of the talks, saying only that "if Europe works based on the nonproliferation treaty, safeguards and international measures, then there will be no room for concern."

He said again that the agenda would focus on Iran's right to enrich uranium, and the talks would be held on a senior level.

Germany, France and Britain have suggested shifting Iran's enrichment activities to Russia, where nuclear material would be enriched only to fuel levels and not to weapons grade.

But Iran said it would enrich uranium and produce nuclear fuel domestically.

On Friday, Mohamed ElBaradei, head of the International Atomic Energy Agency, said the international community was losing patience with Iran over its nuclear program.

"ElBaradei should not politicize issues," Asefi said. "He knows Iran has not diverted in its nuclear program. Some of the words that he said were not correct at all."