Hurricane Irma has pounded the Caribbean, destroying homes and leaving at least 10 people dead.
The rare Category Five hurricane is now heading towards the United States.
Up to a million people have been ordered to flee in the US.
The International Red Cross says 1.2 million people have already been hit by Irma — a number that could rise to 26 million.
The bill for loss and damage from the hurricane could hit $120 billion in the United States and the Caribbean, according to data modelling firm Enki Research.
Irma hit the tiny Caribbean island of Barbuda Wednesday with winds of up to 295 kph (183 mph), according to the Miami-based National Hurricane Centre (NHC).
The small island suffered “absolute devastation,” with up to 30 percent of properties demolished, Prime Minister Gaston Browne said.
One person is known to have died on the island of 1,600 residents, apparently a child whose family was trying to get to safer ground.
Irma then slammed into St Martin, wielding monster winds and torrential rain and wreaking destruction on the tiny Caribbean island, where 60 percent of homes were wrecked.
St Martin is divided between France and the Netherlands.
France said four had died and 50 were injured, two of them seriously.
The Netherlands said the storm killed at least one person and injured several others.
On the Dutch part of St Martin, communications were all but cut off and the damage is “enormous”, according to Dutch Prime Minister Mark Rutte, with an airport destroyed, making relief efforts harder.
The Netherlands said it was racing to provide food and water for 40,000 people over the next five days, while France said more than 100,000 packages of combat rations were en route.
A 200-member French team flew in to Guadeloupe to coordinate rescue efforts, headed by Overseas Territories Minister Annick Girardin.
“It’s an enormous catastrophe. Ninety-five percent of the island is destroyed. I’m in shock. It’s frightening,” a top local official in French St Martin, Daniel Gibbs, said.
Irma tore past the north of American territory Puerto Rico early Thursday, with winds of 295kph, causing power cuts and heavy rain.
More than half of Puerto Rico’s population of three million was without power, with rivers bursting their banks in the centre and north of the island where Governor Ricardo Rossello activated the National Guard and opened storm shelters sufficient for up to 62,000 people.
US VIRGIN ISLANDS
At least four people were killed in the US Virgin Islands, officials told AFP, with the toll expected to rise.
“We lost a significant and a good number of assets… in terms of fire stations, police stations,” Governor Kenneth Mapp said in a Facebook post, adding that the region’s main health facility, the Schneider Regional Medical Centre, lost its roof.
Irma, the longest hurricane on record at this intensity, is forecast to remain a Category Five storm until Saturday, according to the French meteorological agency.
The latest bulletin from the Miami-based National Hurricane Centre put the winds at 175 mph as the storm headed for the Bahamas.
As of Thursday evening the eye of the monster storm was located a few dozen miles north of Haiti, churning past Turks and Caicos and heading for the Bahamas.
Poor Haitians were left to face Irma’s fury alone as authorities showed little sign of preparing for what forecasters said could be a catastrophic event.
Irma could reach the north of Cuba late Friday or early Saturday, before heading on to the southeast coast of the United States, set to hit Florida, Georgia and South Carolina.
Cuba moved 10,000 foreign tourists from beach resorts in the exposed part of the island, and hiked its disaster alert level to maximum.
US President Donald Trump has already declared a state of emergency for Puerto Rico, the US Virgin Islands and Florida, while the southern state of Georgia ordered the mandatory evacuation of the city of Savannah and other coastal areas.
Florida is expecting to face the brunt of the storm from Friday night, with forecasters warning of sea-level surges of up to 25 feet (almost eight metres) above normal tide levels.
On Friday and Saturday, another hurricane, Jose, will pass around 300 kilometres north east of St Martin.
Jose is a Category Two storm, with winds of around 165 kph, according to the NHC.
A third hurricane, Katia, is threatening Mexico’s Atlantic coast and could affect more than a million people in Veracruz state.