KABUL, Afghanistan - President Hamid Karzai's call to suddenly move up elections from late summer to early spring drew cries of "sabotage" Sunday from political opponents who know they can't win the presidency if a vote is held next month.

But few in the capital think Karzai's decree is anything but a political gambit meant to give him the high ground in a tussle for power come May 22, when the Afghan constitution says his five-year term expires.

Karzai released a decree Saturday directing the country's election commission to set a date that adheres to the constitution, which calls for a vote 30 to 60 days before May 22.

The commission in January set the vote for Aug. 20, saying an election could not be held sooner because of security concerns, heavy spring snows in the Afghan mountains and ballot distribution issues.

A commission member said Sunday that August was the earliest the country could hold "free and fair" elections, and that the commission was waiting on an official letter from the president's office to react to his decree.

Some legislators, including one declared candidate, said Karzai should resign in May and let the speaker of the upper house become caretaker president until August elections. A U.S. statement Saturday said August elections would be best.

Afghanistan continues to be plagued by militant attacks since a U.S.-led invasion ousted the Taliban regime in 2001. The Taliban insurgency has strengthened, and last year was the deadliest for U.S. troops since the invasion.

Election officials have said they agreed to hold the election after additional international forces arrived. Thousands more U.S. troops will arrive in the country by August, forces that could help with election security.

But a late summer vote meant the country would face a three-month gap between the end of Karzai's term and the election. Legislators have said they won't recognize Karzai as president beginning May 22, which could throw the country into constitutional crisis.

The constitution gives Karzai at least two options: He could call a state of emergency that would extend his presidency but which eventually would require legislators' co-operation, or he could call a loya jirga -- a grand meeting of Afghan leaders -- to negotiate a solution. Either one likely would require a political deal with his opponents.

While many legislators don't want Karzai in office after May 22, Afghan politicians said Sunday they don't like the idea of early elections, either.

The spokesman for the National Front, a group of opposition legislators, said it would be impossible to hold elections in spring because of security, logistical and financial issues. He called Karzai's move an attempt to "sabotage" the vote.

"If the president wanted to make this kind of decision, he could have done it five or six months ago. Why did he wait so long? Everybody knows it's not possible now," said spokesman Sayyid Agha Hussain Fazel Sancharaki.

Sancharaki said Afghan electoral law calls for candidates to declare their candidacies 75 days before an election, and that moving up the date of the vote would break that law.

A government spokesman said Saturday that Karzai issued the decree after a series of discussions with the Supreme Court.

Afghanistan's historic 2004 presidential election saw 18 candidates run, but many dozens of Afghan power brokers have signalled their interest in running this time, though Karzai is still considered the front-runner.

One declared candidate, Abdul Qadar Emami Ghori, a legislator from Ghor, said Karzai's decree is a way to "cheat" his opponents.

"We don't have enough time to campaign, and some areas are still covered in snow," he said.

Echoing calls from other legislators, Ghori said Karzai should resign in May and the speaker of the upper house, Sibghatullah Mojaddedi, should become caretaker president until August elections.

The election commission said Sunday it had not been officially notified of the decree to explore moving up the vote.

"The commission considered all aspects of conducting free and fair elections in the country with the participation of a large number of people, and it announced that the soonest possible date was the 20th of August," Zekria Barakzai, deputy chairman of the commission, said.

"We are waiting for an official letter from the president's office to react to this," he said, adding that commission members would discuss the issue in the coming days.

The U.S. State Department issued a statement Saturday saying it believes August elections were "the best means to assure every Afghan citizen would be able to express his or her political preference in a secure environment."

International monitors have said it would be difficult, if not impossible, to hold valid elections during the March-April time frame.