Many on St Martin, an island which is divided between France and The Netherlands and known for its vibrant nightlife and pristine beaches, had been concerned about where to go ahead of the second storm.
Marlin said many countries and people have offered help to St. Maarten, but authorities are waiting on the weather conditions to see how this can be co-ordinated.
"So the number of victims has risen to four", he said, after Irma devastated the island, shared with France, on Wednesday. He was scheduled to fly Tuesday to the nearby Dutch islands of Saba and St. Eustatius, which also were hit by Irma, but suffered less damage than St. Maarten.
Meteorologists say heavy rain squalls spawning tornadoes are hitting South Florida part of Hurricane Irma's leading edge.
There are just under 500 troops now in the region, made up of marines, engineers, medics and specialists, including Army and Royal Air Force personnel, the Foreign Office said.
Hurricane force winds extend 70 miles (110 kilometers) out from the 30-mile (48-kilometer) wide storm eye.
Macron said 2,000 people have already been evacuated from St. Martin's French territory and new flights are going to be organized by the end of the week.
"It's been very useful to see for myself what awful damage this storm has done and in this way to also show the population of St. Martin and the governor and prime minister that we stand together here as a kingdom and that we will solve this together", he told reporters.
THE first bottles of water started to arrive on damaged Caribbean islands, leaders started to also focus on longer-term issues arising from Hurricane Irma, including climate change, debt structure and long-term resilience. Others, including St. Thomas in the U.S. Virgin Islands, banned flyovers.
Irma walloped Cuba's northern coast on Saturday as a Category 5 storm and was expected to hit Florida on Sunday morning, threatening massive damage from wind and flooding to the fourth-largest USA state by population.
Two C-130 transport planes loaded with aid including food, water, tents and building materials landed in Sint Maarten on Sunday, and the Dutch Navy said mass distribution would begin on Monday.
Those left behind on St. Thomas and St. John were surviving on whatever they could find as they tried to fix or secure their houses with whatever materials were available.
British Virgin Islands (BVI) Premier Orlando Smith said in a statement: "Rebuilding an entire territory is no small undertaking".
"The biggest problem in Barbuda now is the fact that you have so many dead animals in the water and so on, that there is a threat of disease. Only social media and solidarity worked", said a mother picking up her daughter at Paris's Charles de Gaulle airport.
As for the Dutch side, the Dutch Red Cross described it as a "race against time to get the relief to the affected area".
However as Caribbean leaders met to discuss the situation in the United Kingdom there was loud criticism of Britain's response to Irma. We have seen there are many homes that were built too precariously, with fragile infrastructure.