President Bush has warned of increased pressure against Iran, unless the country agrees to abandon its uranium enrichment program.

At the White House Friday, Mr. Bush said he and visiting Japanese Prime Minister Yasuo Fukuda agreed that a nuclear-armed Iran would threaten the security of the Middle East and beyond. Mr. Bush said he wants to solve the crisis through diplomatic means.

In a report Thursday, the U.N. nuclear agency credited Iran with substantial progress in revealing details about its nuclear program, but said that Tehran continues to defy U.N. Security Council demands to stop uranium enrichment. The enrichment process can be used to make nuclear weapons.

Iranian President Mahmoud Ahmadinejad Fruday called on world powers to admit a mistake in approving two U.N. Security Council resolutions against Iran based on what he said was wrong information.

State television quotes Mr. Ahmadinejad as saying the IAEA report is "relatively realistic" and to a great extent free of the influence of world powers. He also called on the United States to change its behavior.

The United States on Thursday said it intends to continue to push for a third round of U.N. Security Council sanctions against Iran.

A German foreign ministry spokesman says the IAEA report shows that Iran has still not fulfilled its international obligations over its nuclear activities and continues to pursue enrichment work.

A European diplomatic source says a meeting planned for Monday in Europe among Germany and the five permanent U.N. Security Council members has been postponed because the Chinese could not attend.

China and Russia, both permanent U.N. Security Council members, have been reluctant to support more sanctions.

Meanwhile, Russia's state-owned nuclear fuel producer says the IAEA will soon start inspecting and sealing nuclear fuel from Russia that is to be delivered to the Bushehr nuclear power plant that Russia is helping build in Iran.

The United States and its allies accuse Iran of seeking nuclear weapons -- a charge Iran denies.