Western Australia would be prepared to take asylum-seeker families should the federal Government change its position to allow people to resettle in Australia.

Ahead of the closure of the Manus Island detention centre in Papua New Guinea, Premier Colin Barnett says so long as people don't pose a security or safety risk he would welcome them.

"We would certainly accommodate a number of them [asylum seekers] in Western Australia and we'd certainly support them as a state Government," he told ABC TV.

Malcolm Turnbull's Government is under pressure to resolve the fate of more than 800 asylum seekers on Manus Island with the closure of the immigration detention centre.


Immigration Minister Peter Dutton admits there's no firm timeline for the centre's closure, but he hoped it would happen as soon as possible.

"It will take years to clean up this mess," he said.

Labor is demanding the Government find third-party settlement options, and if refugees were to be settled in PNG, to detail which services like education and housing they'd get.

"We need a viable solution ... the Government needs to process these people," immigration spokesman Shayne Neumann said.

The Greens want the men on Manus to be relocated to Australia, saying the decision spells the end of offshore detention.

But Dutton is adamant the 854 men detained there will never make their way to Australia - so should settle in PNG or return to their country of origin. PNG is also set to get a substantial payment to wind the centre down.