In his initial statement Wednesday morning, Mr. Browne suggested he had been receiving reports from Barbuda. But he later clarified that, in fact, the storm had knocked out all official communication systems on the island, rendering officials there unreachable after the storm. As a result, it was not until the afternoon, when the prime minister surveyed Barbuda from the air, that the extent of the devastation became clear.

“What I saw was heart-wrenching — I mean, absolutely devastating,” Mr. Browne told ABS TV afterward, estimating that it would take at least $150 million to return the island to some semblance of normalcy.

“Hurricane Irma would have been easily the most powerful hurricane to have stormed through the Caribbean,” he said, “and it is extremely unfortunate that Barbuda was right in its path.”

Mr. Browne said he had been caught off guard by the utter destruction in Barbuda because it is so close to the comparatively unscathed Antigua. The islands are less than 40 miles apart.

— CARL JOSEPH, KIRK SEMPLE and MAGGIE ASTOR

‘Considerable’ damage in the French Caribbean.

President Emmanuel Macron of France said on Wednesday evening that it was too early to say how badly the islands of St. Martin and St. Barthélemy had been damaged or how many casualties there were. But French officials reported that the death toll was at least two, and Mr. Macron said the aftermath would be “harsh and cruel.”

“We will have victims to lament, and the material damage on the two islands is considerable,” he said after a crisis meeting in Paris, adding that the “entire nation” stood beside the inhabitants of the islands.

Mr. Macron said that emergency services were focusing on re-establishing contact with the affected areas and that rescue operations would be coordinated from the French Caribbean island of Guadeloupe, where the French minister for overseas territories, Annick Girardin, was headed on Wednesday evening.