Herbert Knosowski, Associated Press
President Bush and German Chancellor Angela Merkel on the last day of Bush's visit in Meseberg, Germany.

MESEBERG, Germany — Increasingly tough warnings from President Bush and his European allies have done nothing to temper Iran's stance on its nuclear program, worsening the confrontation over what American officials and others suspect is a covert Iranian plan to build an atomic bomb.

In Germany for meetings with Chancellor Angela Merkel, Bush emphasized again Wednesday that "all options are on the table" in any response to what is suspected of being Iranian research into developing nuclear weapons. Those options would include the possibility of military force, he said.

Even as Bush won new support from the Europeans, President Mahmoud Ahmadinejad of Iran responded by mocking attempts to rein in his country's nuclear program, which Iran maintains is for peaceful development of nuclear energy. Ahmadinejad said in a televised speech in Iran that the West "cannot do anything" and singled out Bush as a lame duck who had failed at every attempt to hurt Iran. "Bush's time is up, and he was not able to harm even one centimeter of our land," the state-run news agency, IRNA, quoted Ahmadinejad as saying.

Iran's intransigence appears to be unifying the Europeans, who remain divided over how severely to punish Iran for not complying with Security Council resolutions that demand that it stop enriching uranium or face sanctions. Iran has called the resolutions illegal and unjustified.

During meetings at Schloss Meseberg, the German government guesthouse here, Merkel joined Bush in calling for more sanctions against Iran if it did not suspend uranium enrichment.

Bush won European support on Tuesday for consideration of additional sanctions, including restrictions on Iran's banks, if the government rejects an incentive package intended to persuade Iranian leaders to suspend uranium enrichment.

But Bush's remarks during an appearance with Merkel also illustrated the distance between them, as Merkel emphasized diplomacy and the need to enforce the current sanctions.