The U.S. has agreed to resettle refugees held by Australia in two offshore detention centers, although the number of people to be offered resettlement was not revealed.

Under Australia's strict border protection laws, any person who attempts to reach the country by boat is sent to the centers on Papua New Guinea's Manus Island and the small South Pacific island nation of Nauru, while their claims for asylum are processed.

Australian Prime Minister Malcolm Turnbull revealed the U.S. deal on Sunday, saying, "This opportunity will be only available to those accepted by the United States on Nauru and Manus now."

"It will not be available to anyone who seeks to come to Australia by people smuggler in the future," Turnbull added.

The U.S. would decide which refugees it took, and would cover the cost of resettlement, according to reports, while no time-frame was given for the resettlements.

It was unclear on Sunday how the deal with the U.S. may be impacted by the policies of President-elect Donald Trump , who took a strict stance on immigration issues during his campaign, including proposing to i mplement a complete ban on Muslim immigration .

According to reports, Australian PM Turnbull was questioned about the potential impact of Trump's election win, but refused to be drawn on the issue, saying that the deal had been done with the current U.S. administration. Trump will be inaugurated on Jan. 20

The Australian Prime Minister did not give details on the number of people to be offered resettlement in the U.S., but state broadcaster ABC reported that it would be offered only to those who had been found to have genuine asylum claims.

Turnbull said priority would be given to the "most vulnerable" groups, such as families, the ABC reported.

Those that did not accept an offer of U.S. resettlement would be offered a 20-year visa to stay on Nauru but no financial support, Immigration Minister Peter Dutton said on Sunday.

The options for people who had not been found to have genuine asylum claims were unchanged: remain in the centers or return to their country of origin, according to reports.

There are about 1,200 people were currently living in the detention centers.

At present, people who reach Australia by boat and are found to be eligible for asylum are offered the opportunity to be resettled in Papua New Guinea or Nauru, but not Australia.

Until late 2013, asylum seekers and migrants frequently attempted to reach Australia from Indonesia, usually by paying people smugglers for passage on boats that were often unseaworthy.

An estimated 1,100 people died making such journeys between 2007, when the Labor government relaxed the country's previously tough border protection policies, and 2013, when the current Liberal government tightened them again.

Australian government statistics show that boat-borne arrivals peaked in 2013 at more than 20,500 people.

The Liberal government's Operation Sovereign Borders, under which it began "turning back" people-smuggling boats to their country of departure, coupled with new rules that denied resettlement to any person who arrived by boat, was introduced in September 2013.

In 2014, the number of people arriving by boat dropped to 160, according to the government's statistics.

On Sunday, the official Operation Sovereign Borders website gave a stark warning to people considering traveling to Australia by boat in the hope of being resettled in the U.S.: "Don't be misled by the lies of people smugglers. You will be intercepted and you will be turned back."

The government has argued that a total ban on Australian resettlement for those who arrive in the country by boat was necessary to prevent people smugglers from putting lives at risk at sea.

But human rights groups have criticized the country for the condition of the offshore detention centers, as well as the length of time many people remain in them while their asylum applications are processed. The issue of detention centers has sparked a number of protests in Australia.

Papua New Guinea said in April that it would close the Manus Island center, after its highest court ruled that it was "unconstitutional." Nauru, however, relies on its detention center as a significant revenue stream.

- Reuters contributed to this report

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