New York, October 4 (RHC-AP) --The recovery of eastern Caribbean islands hardest hit by recent hurricanes, including Dominica, Barbuda, Turks and Caicos, the British Virgin Islands and Anguilla, could cost up to $1 billion, a senior U.N. official said Tuesday.

"It's going to be a large-scale rebuilding effort that will take time," said Stephen O'Malley, the U.N. resident coordinator for Barbados and the Organization of Eastern Caribbean States, "and it will be important to do that right."

He told U.N. correspondents in a phone briefing from Dominica that "we don't have exact figures yet," but for the worst-affected islands the recovery bill will be "half a billion to a billion dollars."

O'Malley said the United Nations, World Bank and Antigua government have conducted a post-disaster needs assessment for Barbuda, whose 1,800 residents were evacuated to Antigua before Hurricane Irma damaged 95 percent of its structures on Sept. 14. And he said a similar assessment will be done in Dominica, which was ravaged on Sept. 18 by Hurricane Maria, a Category 5 storm, probably in about three weeks.

"They want to build back better and they take that very, very seriously — to make sure that that can be done," O'Malley said.

Dominica's Prime Minister Roosevelt Skerrit said he wants to have the world's first "climate-resilient nation."

He made an impassioned case for the world to do more to help vulnerable countries cope with the effects of global warming and urged the U.N. General Assembly 10 days ago to "let these extraordinary events elicit extraordinary efforts to rebuild nations sustainably."