The Federal Government has used reports that some Liberal MPs will cross the floor over cigarette packaging legislation to accuse Tony Abbott of "following the orders of big tobacco".

The Opposition Leader has reacted sceptically to the Government's plans to introduce plain packaging, saying he thinks the move may be counter-productive.

Fairfax newspapers have reported Liberal MP Alex Somlyay, a cancer survivor, has been joined by West Australian MPs Dr Mal Washer and Ken Wyatt in threatening to cross the floor should the Opposition vote against the move.

Opposition health spokesman Peter Dutton says no decision has been taken yet on the Coalition's position, but he wants to see evidence the plan will work.

"We as a Coalition are committed to reducing smoking rates, but we want to make sure we commit to a scheme that will actually work," Mr Dutton said.

But Health Minister Nicola Roxon says it will be good for the public if members of the Opposition support the bill, irrespective of Mr Abbott's position.

"If questions are even being asked by Liberal MPs, I think it's time for Mr Abbott to think about whether he should be so closely following the orders of big tobacco," she said.

Ms Roxon last week said Labor stopped taking donations from tobacco companies in 2004, since which time the Opposition has accepted $1.7 million.

"Mr Abbott needs to kick his habit," Ms Roxon said at the time.

Today she says Mr Abbott, a former health minister, should not "act as the parliamentary arm of the tobacco industry".

"He should be working with the Government to take this step that could save many Australian lives," she said.

A spokesman for Mr Wyatt says the MP "will not be crossing the floor under any circumstances".

Mr Somlyay, through a spokeswoman, declined to comment and ABC News Online was unable to contact Dr Washer.