Opposition Leader Tony Abbott has been warned that backbenchers are lining up to “give him a smack” if he goes it alone on another policy announcement.

Yesterday Mr Abbott was forced to apologise to his colleagues for failing to consult them on his plan to tax big business to fund a 26-week paid maternity leave scheme.

Mr Abbott said he had made a “leader’s call” to press ahead without consulting his shadow cabinet, and said “sometimes it is better to ask forgiveness than permission”.

Western Australian Liberal backbencher Dennis Jensen was highly critical of former leader Malcolm Turnbull for pre-empting the partyroom over an emissions trading policy.

Now he says Mr Abbott has accepted that he needs to consult his partyroom.

“Tony has stated that he doesn’t see this sort of thing happening again,” he said.

“If he does pre-emptively produce a policy again I think that there will be quite a few people lining up to give him a smack.”

Dr Jensen says the big-business levy is not the “preferred option” of many Liberals but it is the only way to fund the scheme because of the current state of the budget.

Outspoken MP Wilson Tuckey says Mr Abbott must adhere to party process.

“I think the message was well and truly delivered, and probably fortuitous so early in his leadership,” he said.

Deputy Opposition Leader Julie Bishop has defended Mr Abbott, saying he took his decision to the partyroom at the first opportunity.

“There are times when leaders make the call on matters, particularly in an election year,” she said.

When asked by reporters this morning if he would guarantee to colleagues that he would not make another “leader’s call”, Mr Abbott said: “I indicated that it’s a risky thing and it should be a rare thing for leaders to make a call like this.”

“It’s very important that we give families a fair go,” he continued.

“Any suggestion that the announcement I made on Monday was some kind of thought bubble is refuted.”

The Opposition’s proposal offers to pay mothers at the rate of their normal salary for six months.

In comparison, the Government’s scheme offers 18 weeks of pay at the minimum wage.

The Government’s scheme is due to start next year but legislation is yet to pass the Parliament and it is now likely it will face pressure from the crossbenches and Opposition to make it more generous.

When asked if the Opposition would vote against the Government’s scheme, Mr Abbott said: “I think what you can expect is as far as possible in the Parliament we will be supporting our policy, not the Government’s policy.”

“My feeling is that the Government is likely to have to do a rapid about-face on this.”

Greens Leader Bob Brown, independent Senator Nick Xenophon and Family First Senator Steve Fielding have praised the Coalition’s plan.

But Finance Minister Lindsay Tanner says the Government is sticking to its proposal.

“It’s always easy for people who do not have the responsibility for managing the nation’s finances to promise everybody more money,” he told AM.

“The minor parties do that all the time, the independent senators are always happy to posture to the gallery, to promise anybody and everybody more money.”

The Government’s legislative agenda is being frustrated by the Senate, with several key pieces of legislation being knocked back.

Mr Tanner says under Mr Abbott the Coalition is becoming more obstructive.

“We’re confronted with an obstructionist opposition that is committed to tearing apart our budget while at the same time attacking us for not getting it back into surplus quick enough,” he said.