TEHRAN – President Ahmadinejad of Iran warned today that a power vacuum is imminent in Iraq and said that Iran was ready to help fill the gap.

“The political power of the occupiers is collapsing rapidly,” Mr. Ahmadinejad said at a news conference in Tehran, referring to American troops in Iraq. “Soon, we will see a huge power vacuum in the region. Of course, we are prepared to fill the gap, with the help of neighbors and regional friends like Saudi Arabia, and with the help of the Iraqi nation.”

Although Mr. Ahmadinejad did not elaborate how Iran could fill a power gap, his bold remarks reflected what may be perceived as Iran’s eagerness for an increasing role on its neighbor’s political scene.

Earlier this month, during a visit here by Prime Minister al-Maliki of Iraq, Iranian leaders said that only an American pullout would bring peace to Iraq and pledged their government would do its best to help stabilize the country.

Mr. Ahmadinejad accused America of interfering in Iraq’s internal affairs, and dismissed American criticism of Mr. al-Maliki’s unsuccessful efforts to reconcile the country’s Sunnis, Shiites, and Kurds.

“They rudely say (the Iraqi) prime minister and the constitution must change,” Mr. Ahmadinejad said. “Who are you? Who has given you the right” to ask for such a change, he added, addressing the American critics of Mr. al-Maliki, who is also a Shiite.

Mr. Ahmadinejad stressed that any American effort to topple the al-Maliki government will fail. Key American Democrats, including Senator Clinton, have called for Mr. al-Maliki to be replaced because his Shiite-dominated government has been unable to forge national unity.

Mr. Ahmadinejad dismissed the possibility of any American military action against Iran.

“I tell you resolutely that there is no possibility, whatsoever, of such a decision in the U.S.,” Mr. Ahmadinejad told reporters. “Even, if they were to decide to do so, they would be unable to carry it out.”

America has accused Iran of being behind attacks on American troops in Iraq – a claim the Iraqi government has only partially backed, saying Iran could have a role in the attacks. Iran has denied the accusations.

On another issue of contention, America and its allies fear Tehran is using its civilian nuclear program as a cover to produce atomic weapons. Iran denies the charge, saying its program is solely geared toward generating electricity.

Mr. Ahmadinejad again today rejected any possibility of Iran suspending its controversial uranium enrichment program, saying it was “out of the question” and that the nation has achieved full proficiency in the nuclear fuel cycle.

“Today, Iran is a nuclear Iran,” Mr. Ahmadinejad said, while vowing Iran was committed to a “peaceful (nuclear) path.”

His comments followed an announcement yesterday by the U.N. nuclear watchdog, the International Atomic Energy Agency, which said Tehran has been offering some cooperation in the agency’s probe of an alleged secret uranium processing project linked by American intelligence to a nuclear arms program.

America criticized the deal with the IAEA, saying it won’t save Iran from a third set of U.N. Security Council sanctions for refusing to halt enrichment.

Mr. Ahmadinejad said Mr. Bush was a “wicked, selfish and arrogant” leader who has abused the Security Council in a push to stop Iran’s nuclear program.

“You saw that your coercion … was futile,” Mr. Ahmadinejad said, addressing Mr. Bush. “You sold out your prestige and stood against a cultured nation. … I recommend that you don’t repeat this ugly behavior.”