TEHRAN: President Mahmoud Ahmadinejad received praise from Iranian opposition politicians and withering criticism from its conservatives after he sent Barack Obama a letter last week congratulating him on winning the U.S. presidential race.

But in a sign that conservatives fear their attacks might inadvertently strengthen a possible opposition candidate in Iran's own presidential vote in June, their criticism has quickly shifted to early support for Ahmadinejad's re-election.

The potential opponent is former President Mohammad Khatami, the moderate whom Ahmadinejad bested in the last elections, in 2005. Khatami has not yet announced his candidacy, but is under pressure from his political allies to run.

On Friday, Obama offered a public reaction to the letter in his first post-election news conference, saying that he would review it and respond appropriately. But he also said that Iranian "support for terrorist organizations has to ease" and that its suspected development of nuclear weapons was not acceptable.

On Saturday, opposition politicians offered praise for Ahmadinejad's outreach. The letter "presented a humane, reasonable and peace-seeking image of Iran," according to the daily newspaper Etemaad.

But other newspapers, as well as conservative members of Parliament, criticized Ahmadinejad.

The hard-line Jomhuri Islami newspaper, in an editorial, said that initiating contact with the United States was among the responsibilities of Ayatollah Ali Khamenei, the supreme religious leader, not of Ahmadinejad. Relations broke off in 1979, after the Islamic Revolution in February and the takeover of the U.S. Embassy in Tehran by hard-line students in November.

The speaker of Parliament, Ali Larijani, referred to Obama's noncommittal response and said the United States "was not moving in the right direction" for improving relations.

Ahmad Tavakoli, a conservative member of Parliament, released a public letter saying Ahmadinejad's unilateral efforts had been met with "arrogant responses" and did not serve the country's dignity.

But by Sunday, the criticism had evaporated, and some conservative politicians had started to praise the letter.

Another conservative member of Parliament, Mehdi Koochakzadeh, said Sunday night that Ahmadinejad's letter was "for the expedience of the regime and with the approval of the supreme leader," according to the Alef Web site, which is run by Tavakoli.

In addition, an editorial in the daily Kayhan, a leading conservative newspaper, said that Ahmadinejad was the "most qualified candidate" for the presidential race despite the criticisms of him. It argued that his achievements were more significant than his failures.

Ahmadinejad is popular in smaller towns and villages, where he has distributed financial aid. In contrast, Khatami would be expected to draw support from large cities.

One analyst suggested that the conservatives were trying to get the opposition to choose a different candidate.

"Maybe the conservatives are signaling to reformers that if they go after Mr. Khatami, they would get unified behind Ahmadinejad despite their differences with him," said Badr-al-sadat Mofidi, the deputy editor of the opposition Kargozaaran daily. "The unity among conservatives can change if the reformers do not nominate Mr. Khatami."

In what appeared to be another signal of easing pressures on Ahmadinejad, several members of Parliament have indicated that they would vote for his nominee to fill the post of interior minister. Parliament fired Interior Minister Ali Kordan last week for lying about an honorary doctorate he said he had received from Oxford University.

The nominee, Sadeq Mahsouli, is a close ally of Ahmadinejad. But the previous Parliament - which was more closely aligned with the president - rejected Mahsouli's candidacy for the post of oil minister after doubts were raised about the source of his vast fortune.

Mahsouli is a former commander of the Revolutionary Guards, which have used their vast power in Iran to control parts of its economy.

Ahmadinejad is suffering politically from the damage to the Iranian economy caused by high inflation and a sharp drop in oil prices. Sixty economists warned in a public letter to the president that his hostile attitude to the rest of the world was causing lost trade and investment for the country, newspapers reported Saturday.

The letter criticized the government for spending too much of the oil revenues, and for policies that the economists said had deprived the country of foreign investment.

It said that the UN Security Council sanctions over Iran's refusal to suspend sensitive uranium enrichment activities had cost the country billions of dollars.