UPDATED 1.08pm: Protesters have climbed on top of the Australian Prime Minister Tony Abbott's Manly electorate office.

Four people - from the group Hunger for Justice - have managed to clamber up onto the roof of the three level building in support of detained asylum seekers.

They are speaking with police on the scene.

It comes as as leadership tensions engulf Australia's federal Liberal Party.

Bishop backs under-fire Abbott

Julie Bishop has reiterated her confidence in Tony Abbott, as leadership tensions engulf Australia's federal Liberal Party.

There are reports the Foreign Minister and Communications Minister Malcolm Turnbull are weighing up a leadership challenge.

Abbott's coalition is now well behind Labor in the polls and the Prime Minister's personal approval rating is down to 27 percent.

But Mrs Bishop is unequivocal about her support.

"Yes, Tony Abbott does have my support.

"He will be giving a significant speech today at the National Press Club. He will outline a strategic direction for us in the leadup to the next election."

Australia correspondent Steve Price told Newstalk ZB's Mike Hosking there are two in the running for the leadership - Julie Bishop, or Malcolm Turnbull.

"Stories today are suggesting that Malcolm Turnbull has probably got his head in front and that the former immigration minister Scott Morrison would end up as treasurer."