Refugees bound for US within weeks

More than 200 refugees being held on Manus Island and Nauru are expected to depart for the United States within weeks.

The group will join more than 50 refugees who have already arrived in the US after being accepted under a resettlement deal expected to offer up to 1250 places for those in Australia's offshore detention centres.

"Obviously months beyond that there'll be others that will be able to leave Manus and Nauru and go to the United States," Immigration Minister Peter Dutton told ABC radio on Wednesday.