A push to decriminalise abortion in Queensland is set to fail, with the state's LNP Opposition vowing to block the move because it says the proposed reforms are deeply flawed.

Key points: Independent Rob Pyne wants to decriminalise abortion in Queensland

Independent Rob Pyne wants to decriminalise abortion in Queensland Bills likely to fail due to lack of Parliament support

Bills likely to fail due to lack of Parliament support Pyne determined to continue campaign

Independent Rob Pyne's two bills to legalise abortion will be debated on Wednesday.

Labor is allowing its MPs a conscience vote, meaning members are not locked into adopting the same stance as party colleagues.

LNP MPs have also been offered a conscience vote on the bills, but Opposition Leader Tim Nicholls said his members would not back either.

"After this discussion every single member of the LNP party room indicated that, in good conscience, they cannot support these bills," Mr Nicholls said in a statement.

Because not all Labor MPs will support abortion, at least some LNP MPs need to vote in favour of it for the reforms to succeed in Queensland's tightly-balanced Parliament.

The bills were introduced months apart — the first sought to remove abortion criminal code, but does not put any restrictions on when in a pregnancy an abortion may be performed.

At the time, Mr Pyne said that was deliberate as he wanted MPs to decide on a cut-off in a later stage of the debate.

Months later he introduced a second bill which included regulations around who can perform a termination, and allowed for doctors to conscientiously object.

It also allowed abortions to be performed when a woman is more than 24 weeks pregnant, but only if two doctors agree continuing the pregnancy is a greater risk to the woman's physical or mental health than if it were terminated.

Laws could create 'further risk and uncertainty': LNP

Abortion has been on Queensland's Criminal Code since 1899, and women and doctors can be prosecuted for accessing or performing a termination.

However in 1986, a court ruled that abortion is lawful if there is serious danger to the mother's life or her physical or mental health.

Mr Pyne believes his changes would destigmatise abortion, but his method of reforming the law has been criticised.

Deputy Premier Jackie Trad (right) and Rob Pyne (left) have been vocal supporters of decriminalising abortion. ( ABC News: Giulio Saggin )

Queensland Parliament's Health Committee said the initial bill's push to decriminalise abortion without suggesting regulations showed a "lack of rigour and foresight in policy development".

It also raised the possibility one bill could pass, but the other fail.

Professor Lindy Willmott from the Australian Centre for Health Law Research told the committee that would create uncertainty.

"It would have the effect that it would be more difficult in Queensland for a person in the first 24 weeks gestation period to obtain a termination than after 24 weeks," she said.

Mr Nicholls singled out the "the failure to properly and holistically deal with such an important issue" as the reason his MPs could not support the bills.

"The second bill attempts to correct the failures of the first bill but falls well short," Mr Nicholls said.

"It creates further risk and uncertainty as shown in the Parliamentary Committee report — this doesn't help anyone.

"The most recent Parliamentary Committee report makes it very clear that if a woman in Queensland wants or needs an abortion she can obtain one safely through her doctor."

Pyne determined to push reforms through

Mr Pyne said he would be "ceaseless" in his pursuit to change the state's laws on abortion, even if his attempt this week failed.

He criticised the LNP for its decision to block his bills, but said he was pleased Labor would allow its members a conscience vote.

"While some of the extremist groups are very vocal, about one in four Queensland women have had this procedure at some point.

"They're not going to forget when they go to vote at the ballot box if people and members of Parliament want to classify them as criminals."

Deputy Premier Jackie Trad hit out at Mr Nicholls and the LNP, saying they would have put forward amendments if they wanted the bills passed instead of vetoing them.

"This is Tim Nicholls at his weakest best," she said.