Haitian President Jean-Bertrand Aristide has called for international help to end a rebel insurgency designed to topple him.

Mr Aristide made the call hours before the expiry of a deadline for the rebels to respond to a US-backed peace plan.

The rebels control much of the north and have vowed to move on the capital.

"Should those killers come to Port-au-Prince, you may have thousands of people who may be killed," Mr Aristide told a news conference.

The three-week-old insurgency in Haiti has left at least 70 people dead.

France, the former colonial power, is also stepping up its efforts to help end the crisis.

French Foreign Minister Dominique de Villepin will meet representatives of the Haitian government and political opposition in Paris this week.

"We are in a race against time to stop the violence," Mr de Villepin told French radio.

Lawlessness

Rebel factions have already overrun the country's second city, Cap-Haitien and the territory under their control is said to be rapidly descending into lawlessness.

The insurgents, who have no links to the political opposition, say they will continue their action until all of Haiti is "liberated".

Government supporters in Haiti have set up roadblocks at key points in the capital, Port-au-Prince, and erected barricades at the presidential palace.

Amid the escalating violence, the UK Foreign Office on Tuesday advised Britons to leave Haiti because of the "highly volatile security situation" in the Caribbean country.

Several other governments have already encouraged their nationals to leave, including the US, which has also sent marines to protect its embassy.

Boat people

"We need the presence of the international community as soon as possible," Mr Aristide told journalists.

The president said the rebels had attacked another town, Port-de-Paix, even though media reports said the attack had been carried out by a disgruntled street gang of criminals who had had trouble with the police.

"The criminals and terrorists went to the north, to Port-de-Paix, and burned private and public buses, killing people," Mr Aristide said.

And he warned that the conflict might create more boat people - as Haitians might take to the seas to reach the US coast in Florida.

"Unfortunately many brothers and sisters in Port-de-Paix will not come down to Port-au-Prince, they will take to the sea, they will become boat people."

"I want Haitians to stay in Haiti so they can vote in elections, maybe before next November," the president said.

US Secretary of State Colin Powell has given Haitian opposition leaders until 2200 GMT to sign up to a power-sharing plan - but they are expected to reject it, says the BBC's Stephen Gibbs in Port-au-Prince.

Haiti's neighbours have said they will not accept the overthrow of the democratically elected Mr Aristide, but his opponents accuse him of rigging elections four years ago and have demanded he stand down.