Labor will double Australia's refugee intake to 27,000 people as part of a suite of new immigration policies, which also includes turning back asylum seekers boats.

And while some in the party's Left faction are preparing for a fierce fight over the issue, at least one factional powerbroker from the Left - who asked not be named – predicted the adoption of a boat turn-backs policy would be allowed by this weekend's national conference.

"[Labor leader Bill Shorten] won't lose it [the vote on turn-backs] I don't think, though there will be substantial opposition. But some in the Left actually support turn-backs," the Left powerbroker said.

However, Labor backbencher and former speaker Anna Burke warned voters may abandon the party following Mr Shorten's decision.

Joining a chorus of opposition from within the party, Ms Burke criticised the Labor leader for pre-empting this weekend's debate and said: "I'm not in a position to support this policy."

She said a genuine regional processing centre was the answer to stop people smugglers, not turning back boats, which would be dangerous for asylum seekers and the Australian navy.

Asked if Labor voters would switch to the Greens, Ms Burke said she did not see it as a Left-Right issue and that Liberal voters also cared about the treatment of asylum seekers. "But I do think there will be a lot of people this morning asking whether they will be able to vote for Labor."

The rise in Australia's refugee intake to 27,000 – it is currently 13,750 - is part of a suite of asylum seeker policies that will be debated at national conference.

Those policies are contained in the draft national platform and also include the abolition of temporary protection visas, and greater transparency and independent oversight of detention centres.

The 27,000 figure, which was recommended by the expert panel on asylum seekers led by former Defence chief Angus Houston, is likely to be adopted by the conference.

This and other measures are seen internally as both morally the correct thing to do and as something of a peace offering to the party's Left, much of which is opposed to boat turn-backs.

The adoption of boat turn-backs – long-flagged by Mr Shorten and his immigration spokesman Richard Marles – is far more contentious.

The numbers on the conference floor – there are 197 Right-aligned delegates, 196 Left-aligned delegates and 4 non-aligned delegates – mean the vote on turn-backs will be tight.

A loss for Mr Shorten would almost certainly be fatal for his leadership.

Mr Shorten flagged on Wednesday night that he would have more to say about the rise in the refugee intake.

"I do believe we can probably take more refugees," he said.

He told the ABC's 7.30 program that Labor had decided to adopt the turn-back policy because the party "wants to defeat the people smugglers and we want to prevent drownings at sea".

Greens immigration spokeswoman Senator Sarah Hanson-Young said on Thursday that Mr Shorten had "kowtowed" to Prime Minister's policy of turning back asylum seeker boats. Labor had become a "thin-veiled image of the Liberal party" particularly on refugees.

"There is no leadership being shown here. It's the coward's way to back fear over an anti-refugee campaign run by Tony Abbott. It's the coward's way to play politics with people's lives 
rather than stand up and call for a humanitarian response."

Senator Hanson-Young rejected the idea that turning back boats prevented people dying at sea in the long term.

"Pushing boats away doesn't save lives, it pushes people to die in someone else's waters or leaves them locked in a situation, trapped where they can't escape danger. Whether that's in Malaysia, Indonesia or many of their homelands."

Refugees continued to need Australia's protection, she said.

She said Mr Shorten's decision to change his stance on turning back boats was purely political and lacked a humanitarian response to refugees, such as the European Union's, whose naval ships were rescuing people at sea and bringing them ashore to process their claims.

"Where is the response on search and rescue? Where's the detailed policy on a regional framework?"

In March, Labor's leading member of the Left - Mr Shorten's deputy and the ALP foreign affairs spokeswoman Tanya Plibersek -  said boat turn-backs had damaged Australia's relationship with Indonesia.

"We certainly have been opposed to turn-backs," Ms Plibersek told Sky News. "Tony Abbott can't get a phone call returned from the Indonesian president – it has affected our relationship with Indonesia in the past. It has not been good for it."

with Jane Lee

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