CANBERRA, Australia — Barring some unexpected development, none of the refugees held in detention camps on the Pacific islands of Nauru and Manus are likely to be resettled in the United States before President-elect Donald J. Trump takes office, Australian and American officials said this week.

The election of Mr. Trump, whose harsh talk about immigration and Muslims was central to his campaign, leaves in doubt the deal the two countries recently struck to move some of the hundreds of people who were banished to the camps by Australia, after being intercepted at sea trying to reach its shores. Many of the detainees are Muslims.

The issue is a contentious and emotional one in Australia, whose government has pledged never to accept a migrant who tries to come to the country by boat. The stated purpose of the so-called Pacific solution, in which such people are housed indefinitely on offshore islands, is to discourage human traffickers, who often pack migrants into rickety boats for the journeys, some of which have ended in mass drownings.

But conditions on those islands are dire. On Friday, a United Nations envoy visiting Australia said that daily life for detainees on Nauru was cruel, inhumane and degrading. Human rights groups have reached similar conclusions about conditions on both islands.