Tanya Plibersek has sought to show solidarity with Labor's new position on asylum seeker boat turnbacks, saying the party has struck a "terrific position".
The deputy Labor leader, from the NSW Left, avoided personally voting on the proposal to allow a future Labor government to adopt the policy at the ALP national conference on Saturday, instead handing her vote to a proxy.
Quizzed on her position by journalists on Sunday, Ms Plibersek said Labor's position was "humane, compassionate and sensible".
She "could not be prouder" of Labor's policy, which includes a plan to double Australia's humanitarian intake.
"We can bring more people to Australia and bring them here safely," she said.
Labor senator Kim Carr said Ms Plibersek had strongly supported the position "articulated on behalf of the whole shadow cabinet" by Labor Leader Bill Shorten during Saturday's debate on the issue.
"Tanya spoke very strongly in support of the shadow cabinet's position at the various meetings I attended," Senator Carr told Sky News on Sunday.
But the government's immigration minister Peter Dutton questioned the level of Ms Plibersek's support given she had abstained from the process, saying it demonstrated how fraught things could become if Labor got into government.
He was also critical of Labor's new approach, calling it "dodgy" and "watered-down".
"People who characterise this as somehow the Labor party agreeing to a carbon copy of the government's successful policy ... completely misreads the situation," he told Sky News.
"It's not about the stern approach taken by the government, it is now a discussion about turn-backs."
Labor frontbencher Anthony Albanese, also from the NSW left, opening voted against turning back asylum seeker boats.
"If people were in a boat, including families and children, I myself couldn't turn that around," he told ABC television.
Mr Albanese acknowledged it was now part of Labor's policy platform but "I don't believe the boats will come".
Joel Fitzgibbon, from the NSW Labor Right, agreed that having to enforce turn-backs was "all hypothetical"
"We've accepted the current package works ... so let's leave the package in one piece and make sure they don't start coming again," he told Network Ten.
Mr Fitzgibbon could not say how much Labor's asylum seeker policy would cost the federal budget.
