Joe Hockey has pointed the finger at ministerial colleagues angry about having to find savings in their portfolios to explain speculation Malcolm Turnbull could replace him as Treasurer.

Mr Hockey also said it was up to the other members of the Abbott government, not just him, to do the hard work in selling the budget to the public.

Mr Hockey said he faced a tougher job than any treasurer in the past 15 years and that predecessors Peter Costello and Wayne Swan were able to hand money to taxpayers "without constraint".

Mr Hockey's comments come at the end of a week dominated by headlines about tension between Prime Minister Tony Abbott and Foreign Affairs Minister Julie Bishop and infighting in the office of Defence Minister David Johnston.