TEHRAN, Iran - Iran's president yesterday dismissed a year-end deadline set by the Obama administration and the West for Tehran to accept a U.N.-drafted deal to swap enriched uranium for nuclear fuel. The United States warned Iran to take the deadline seriously.

Mahmoud Ahmadinejad also accused Washington of fabricating a purported secret Iranian document that appears to lay out a plan for developing a critical component of an atomic bomb.

Ahmadinejad's remarks underscored Tehran's defiance in the nuclear standoff - and also sought to send a message that his government has not been weakened by the protest movement sparked by his disputed reelection in June.

He spoke a day after the latest opposition protest by tens of thousands during a funeral for the dissident cleric Ayatollah Hossein Ali Montazeri who died Sunday.

President Obama has set a rough deadline of the end of this year for Iran to respond to an offer of dialogue on the nuclear issue. Washington and its allies are warning of new, tougher sanctions on Iran if it doesn't respond.

The U.N.-proposed deal is the centerpiece of the West's diplomatic effort. Under the deal, Tehran would ship most of its stockpile of low-enriched uranium abroad to be processed into fuel rods, which would ease the West's fears that the material could be used to produce a nuclear weapon.

Iran, which denies it seeks to build a bomb, has balked at the deal's terms.

The international community can give Iran "as many deadlines as they want, we don't care," Ahmadinejad said in a speech to thousands of supporters in the southern city of Shiraz.

"We told you that we are not afraid of sanctions against us, and we are not intimidated," he said, addressing the West. "If Iran wanted to make a bomb, we would be brave enough to tell you."

The Obama administration responded sternly. "It is a very real deadline for the international community," said White House press secretary Robert Gibbs.

In Paris, Foreign Minister Bernard Kouchner said chances of finding a diplomatic solution to the nuclear standoff with Iran were "never very significant" and that in the "worst case," France will bring up the issue of new sanctions on Tehran.

In a separate interview with ABC News, Ahmadinejad accused the United States of forging the document that appears to describe an Iranian work plan for developing a neutron initiator, a key component in detonating a nuclear bomb.

He said accusations that Iran seeks a weapon has "turned into a repetitive and tasteless joke." The comments were aired Monday night.

The memo was first reported in the Times of London. U.S. officials have said it's unclear whether the document is authentic.

In his speech yesterday, Ahmadinejad also shrugged off Iran's continued political turmoil since the June election.

He said the West mistakenly believed that Iran "has been weakened."

"The people of Iran and the government of Iran are 10 times stronger than last year," he said.

Iran says its nuclear program is intended only to generate electricity and that it has a right to proceed with uranium enrichment, which the United Nations has demanded it suspend. The process can produce low-enriched uranium used to fuel a nuclear reactor - or higher enriched uranium, which is the basis for building a nuclear warhead.

Under the deal brokered by the U.N. nuclear watchdog agency last month, most of Iran's low-enriched uranium would be shipped abroad, where it would be enriched further to produce fuel rods. The rods would then be returned to Iran for use in a research reactor in Tehran, but it would not be possible to enrich them further to a high enough level to build a bomb.

Iran's response has been unclear, with officials floating a number of alternative ideas for a swap - but not fully accepting the terms.