TEHRAN, Iran -- Conservatives and reformists are openly challenging President Mahmoud Ahmadinejad's hard-line nuclear diplomacy -- an unusual agreement across Iran's political spectrum, with many saying his provocative remarks have increasingly isolated their country.
The criticism comes after the U.N. Security Council voted unanimously last month to impose sanctions on Iran for refusing to halt uranium enrichment. Some critics view the sanctions as an indication that Iran must change its policy.
After a year of silence, reformists are demanding that Iran dispel fears that it is seeking to build atomic weapons, pressing for a return to former President Mohammad Khatami's policy of suspending enrichment, a process that can produce the material for either nuclear reactors or bombs.
"Resisting the U.N. Security Council resolution will put us in a more isolated position," said the Islamic Iran Participation Front, the largest reformist party.
Ahmadinejad's popularity already was weakened after his close conservative allies were defeated last month in local elections, which were widely seen as a referendum on his 18 months in power.
Even some conservatives warn his confrontational tactics are backfiring.
"Your language is so offensive ... that it shows that the nuclear issue is being dealt with a sort of stubbornness," the hard-line daily Jomhuri-e-Eslami said in a recent editorial.
Some lawmakers on both sides of the political spectrum are considering impeaching Foreign Minister Manouchehr Mottaki if the Security Council approves more resolutions against Iran.
"That all 15 members of the Security Council unanimously voted, against the claim by our diplomatic apparatus that there was no unanimity against Iran, shows the weakness of our diplomatic apparatus," said Noureddin Pirmoazzen, a reformist lawmaker.
Despite the criticism, Ahmadinejad has remained defiant, escalating Iran's nuclear standoff with the United States and its allies. He has repeatedly refused to suspend enrichment, even under pressure from its trade allies Russia and China. Iran insists its nuclear program is for peaceful purposes.
, denying allegations from the U.S. and its allies that it is secretly trying to build a bomb.
On Saturday, Ahmadinejad met with fellow U.S. critic Venezuelan President Hugo Chavez at the start of a Latin America tour -- his second such visit in four months. Critics say the trip was partly aimed at diverting attention from the disapproval at home.
Ahmadinejad has also distanced some of his conservative base by calling for Israel to be "wiped off the map" and hosting a conference last month that cast doubt on the Holocaust. Many feel he has spent too much time defying the West and too little tackling Iran's domestic issues.
"The sanctions imposed on Iran are believed to have been partly due to Ahmadinejad's anti-Israel rhetoric and the Holocaust conference," said political analyst Iraj Jamshidi.
The president's tactics, Jamshidi said, have turned Iran's nuclear program from a source of national pride to a hotbed of dispute.
"Ahmadinejad made two major claims in his presidential campaign: to bring oil revenues to the kitchen of every Iranian family and to protect Iran's nuclear achievements. He failed in both," he said.