Abbott olive branch to his MPs

Trade Minister Andrew Robb says Tony Abbott's broken promises and missteps are a "big part" of the Government's problems but has urged Liberal MPs to give the Prime Minister a second chance.

In a frank assessment of the coalition's predicament, Mr Robb said the Government sprang too many surprises last year, offered solutions before identifying the problems and had not "ventilated" controversial options with the public.

With Mr Abbott's detractors saying there is a 50-50 chance of a leadership spill on Tuesday when the party room meets for the first time this year, Mr Robb said a move against the PM would ignore the "serious internal attempt" not to repeat last year's errors.

Mr Robb acknowledged that Mr Abbott's belated acknowledgment of broken election pledges, controversy over his chief of staff Peta Credlin and the knighting of Prince Philip had contributed to the coalition's problems.

He identified the two biggest surprises for voters as the proposed $7 Medicare co-payment and university changes that would cut funding 20 per cent and deregulate fees.

"Many people woke up after the Budget and found two very large packages looking to provide a solution to problems that they weren't aware we had," he said.

Mr Robb said the Government had not developed an argument for the need for "behavioural changes in health" and for more focus and specialisation in universities or how to deliver these changes.

He said Mr Abbott spent two weeks taking "soundings" from MPs and that the PM remained the best leadership option.

"I have no doubt about that but I think we should give him the opportunity to also prove it," Mr Robb said. "If something happened on Tuesday that led to a spill, we would look like a bunch of amateurs."

Mr Abbott said he remained confident he would survive next week but it is understood he will implement more changes to further placate colleagues' concerns.

Ms Credlin will no longer attend Cabinet meetings and Budget proposals will be "road-tested" properly before being unleashed and with more input from the backbench.

Malcolm Turnbull, who many Liberals are privately willing to challenge Mr Abbott, last night said the PM had "utter loyalty and consistency" from his ministers.

"There is no tension between Tony and any of his senior colleagues," Mr Turnbull said.

"It is a very, very cohesive team."