The Bush administration believes the best way to avoid an armed rebel takeover in Haiti is for President Jean-Bertrand Aristide (search) to resign and transfer power to his constitutional successor, a senior U.S. official said Friday.

Meanwhile, the Marine Corps indicated that it is preparing a possible mission to waters off the coast of Haiti. Any such deployment would be aimed at deterring a potential refugee crisis and to protect the estimated 20,000 American citizens in Haiti.

Secretary of State Colin Powell signaled that direction in administration policy in remarks Thursday night, said the U.S. official, who discussed the situation only on grounds of anonymity.

It was not clear whether the more assertive U.S. policy has been communicated directly to Aristide.

President Bush decided to support a tougher line on Aristide following an extended debate within the administration over how to proceed in the face of the gathering crisis in the Caribbean nation, the official said.

Without pressure, this official added, Aristide may elect to try to remain in power even if his defeat at the hands of armed opponents seems certain.

If Aristide is forcibly removed, Haiti would be run by an illegal regime with no international standing and little possibility of securing popular support.

Earlier this week, France voiced support for Aristide's early departure and Powell, in his comments Thursday, questioned Aristide's ability to govern effectively during the two years that remain in his term of office.

If Aristide steps down, the constitutional successor would be Supreme Court Chief Justice Boniface Alexandre (search). In an interim period before elections are held, a broad-based government would be formed consistent with a peace proposal set forth a month ago by the Caribbean Community (search), the official said.

Bush declined comment Friday on whether he would support an Aristide resignation.

"We're interested in achieving a political settlement," Bush said during an Oval Office photo opportunity with German Chancellor Gerhard Schroeder.

If Bush decides a troop deployment is necessary, a likely choice would be to send the 24th Marine Expeditionary Unit, whose 2,200 Marines are based at Camp Lejeune, N.C.

The unit's Web site quoted Lt. Gen. H.P. Osman, commander of the 2nd Marine Expeditionary Force at Lejeune, as telling Marines of the 24th MEU last Friday that they might be called on in Haiti.

"Things are bubbling right now in a nation in our own hemisphere, and ... you're the Marines I'm going to be looking at to possibly answer that contingency," Osman was quoted as saying. The revolt in Haiti and the potential requirement to protect American citizens there is just one example of the many missions for which Marines must be prepared, the Web site said.

Powell, who has made no secret of his disregard for Aristide, said Thursday: "Whether or not he is able to effectively continue as president is something he will have to examine carefully, in the interests of the Haitian people."

Powell suggested that Aristide should take into account Haiti's current reality, a reference to the popular uprising that has threatened his hold on power.

"President Aristide has the interests of the Haitian people at heart," Powell said. "I hope he will just examine the situation he is in and make a careful examination of how best to serve the Haitian people at this time."

Powell said the United States spent a lot of money attempting to build democratic institutions in Haiti after U.S. military forces reinstated Aristide in 1994 from a military regime that had deposed him.

"But unfortunately, it didn't stay together," Powell said. "Corruption came into play, inefficiency came into play, cronyism came into play and the whole political tapestry of the country came apart."

Aristide had no direct role in governing Haiti after his first term — interrupted by three years of military rule — ended in 1996. He was out of office for five years and was re-elected in 2001. He says he is determined to complete the remaining two years of his term.

Democratic lawmakers on Friday stepped up criticism of Bush's handling of Haiti. Sen. Christopher Dodd, D-Conn, said "one way or another, the United States is going to have to get involved to resolve this mess.

"We can do it sooner — and minimize the loss of life and property destruction — or we can do it later when we will be sending body bags to dispose of the dead and Coast Guard cutters to pick up Haitians at sea," he said.

Armed Haitian rebels who have seized control of much of the country said they were closing in on Port-au-Prince, the capital.

Powell told the Senate Budget Committee at a hearing Thursday that the United States would be willing to join an international security force to back a political settlement in the Caribbean nation, if one is reached.