TEHRAN, Iran - Faced with the prospect of new sanctions because of Iran's nuclear defiance, President Mahmoud Ahmadinejad said Saturday that new penalties would only strengthen the country's technological progress by encouraging it to become more self-sufficient.

In a speech, Ahmadinejad also rejected President Barack Obama's offers of engagement, saying "three or four beautiful words" don't mean U.S. policies have changed under his administration.

"They say they have extended a hand to Iran, but the Iranian government and nation declined to welcome that," he said. "What kind of hand did you extend towards the Iranian nation? What has changed? Did you lift sanctions? Did you stop propaganda? Did you reduce the pressure?"

White House spokesman Bill Burton said Saturday the U.S. administration would have no comment on the Iranian president's remarks.

Obama said Thursday that six world powers dealing with Iran's nuclear program will develop a package of serious new punitive measures over its refusal to halt uranium enrichment in coming weeks.

China has not confirmed U.S. reports that it has dropped its opposition to possible new U.N. sanctions against Iran. China has veto power in the U.N. Security Council and its support would be key to passing a resolution against Iran.

Iran's top nuclear negotiator, Saeed Jalili, is in China in the hopes of winning assurances from Beijing that it will oppose sanctions.

The U.S. and some of its allies have accused Iran of seeking to use its civilian nuclear program as a cover to develop nuclear weapons. Iran has denied the charge, saying its nuclear program is geared towards generating electricity, not bombs.

Three rounds of earlier United Nations sanctions have already been imposed.

Iran's economy has suffered over the past year, and parliament approved a cut in subsidies that keep fuel prices low, a further blow to Iranians already experiencing high unemployment and inflation.