The former president, who fled Port-au-Prince on Sunday, has said he was the victim of a “coup d’etat”.
US Secretary of State Colin Powell said Mr Aristide had gone into exile “willingly, and that’s the truth”.
Meanwhile, the Caricom group of 15 Caribbean nations holds talks in Jamaica later on Tuesday to discuss sending peacekeepers to Haiti.
The meeting follows comments by the US that its troops will provide immediate security but the problem must be shared by the whole American continent in the longer term.
An advance guard of US Marines and French soldiers is in Port-au-Prince – part of an international force authorised by the United Nations, expected to number less than 5,000.
Mr Powell reportedly let Mr Aristide know the US would not protect him if rebels captured the Haitian capital, the Associated Press (AP) news agency said.
Mr Powell communicated the message via Ronald Dellums, a former congressman now working as a Washington lobbyist for Mr Aristide, AP reported.
But the UN said it was satisfied with the manner of Mr Aristide’s departure.
“We have no problem. He resigned,” UN spokeswoman Marie Heuze said.
Earlier, friends of Mr Aristide in the US had alleged that he was abducted by American agents – allegations Mr Powell called “absolutely baseless, absurd”.
The US state department has begun working on the creation of a “council of elders” including Mr Aristide’s interim successor, Chief Justice Boniface Alexandre, to prepare for new elections and regroup the police force.
Mr Aristide is now in the Central African Republic with his wife and children after leaving Haiti on a US plane, a day before rebels entered Port-au-Prince.
Rebel leaders say they hope the new government will reinstate the army, which was disbanded in 1995 by Mr Aristide.
‘Thousands may get killed’
In an interview with CNN television, Mr Aristide said he had been in his palace in Port-au-Prince when “American agents” arrived to take him to the airport.
“And when I asked how many people may get killed, they said thousands may get killed.”
He claimed he was unaware of where he and his family were being flown to.
“We spent 20 hours in that plane without knowing where we were going, without having the right to contact our people,” he said.
Luis Moreno, the deputy chief of mission at the US embassy in Port-au-Prince, said six US security guards had been present at the departure and that nothing had been done to coerce the president into leaving.
“At no time did anyone threaten him or coerce him, it was all very courteous and polite,” Mr Moreno said
The CAR Foreign Minister, Charles Wenezoui, has said that the former Haitian leader is not a prisoner, but a free man.
The BBC’s Justin Webb in Washington says Mr Aristide’s supporters in America, including the Democratic party activist the Reverend Jesse Jackson, are outraged.
They are calling for an inquiry into whether the US Central Intelligence Agency had a role in the rebellion which led to the downfall of Mr Aristide and his democratically elected government.