At least nine people died after Hurricane Irma hit Caribbean causing widespread destruction and reducing buildings to rubble.
The small island of Barbuda is said to be “barely habitable”. Officials warn that St Martin is almost destroyed, and the death toll is likely to rise.
Irma, a category five hurricane, the highest possible level, is passing north of Puerto Rico.
Two other storms have strengthened to become hurricanes.
More than half of St Martin’s three million residents were without power as Irma caused heavy downpours and strong winds. Officials have said that power could be cut off for several days.
The most powerful Atlantic storm in a decade had wind speeds of 185mph and was expected to pass near or just north of the coast of the Dominican Republic on September 7.
Hurricane Irma first hit the dual-island nation of Antigua and Barbuda. At least one death, of a child, was reported on Barbuda, where PM Gaston Browne said about 95% of the buildings had suffered some damage.
“It’s absolute devastation,” he said after flying over the island, home to some 1,600 people.
“The island is literally under water. In fact, I’m of the view that, as it stands now, Barbuda is barely habitable.”
However, Antigua, with a population of 80,000, escaped major damage, with no loss of life, he said earlier.
Officials have confirmed at least eight deaths and considerable damage in the French territories of St-Martin and Saint Barthélemy, popularly known as St Barts.
Almost 95% of the island is destroyed, according to officials.
Significant damage was also reported in the Dutch section of St Martin, known as Sint-Maarten.
Sint-Maarten’s airport, the third largest in the Caribbean, has been destroyed.
The Dutch defense ministry said: “The picture is of many uprooted trees, houses without roofs and pleasure boats on land.”
According to media in the Netherlands, the Dutch navy has sent two ships from nearby Aruba and Curacao to assist locals.
President Donald Trump said he and his aides were monitoring Irma’s progress.
“But it looks like it could be something that will be not good. Believe me, not good,” he told reporters at the White House.
Projections suggest Irma could hit Florida on September 10.
Officials started evacuations of tourists and residents of Florida Keys, a resort archipelago.
Flights to and from several airports in Florida were being suspended, while Orlando’s international airport said that commercial flights would stop from 17:00 local time on September 9.
A state of emergency had been declared for Florida, Puerto Rico and the US Virgin Islands, mobilizing federal disaster relief efforts.