Queensland is expected to pass legislation to decriminalise abortion next week, after the opposition Liberal National party decided to allow its MPs a conscience vote.

The decision, announced after a lengthy party room meeting on Tuesday afternoon, will pave the way for the removal of abortion from the 1899 criminal code.

The laws, which will be put to the parliament next week, allow for abortion up to 22 weeks gestation and provide safe access zones around abortion clinics.

The opposition leader, Deb Frecklington, said she was “not of a conscience” to support the bill and would speak further during the debate in parliament.

“It has been a longstanding position of the LNP party room that matters about the creation and ending of life are treated as matters of conscience,” Frecklington said in a statement.

Last month the president of the LNP, Gary Spence, reportedly told MPs they could lose preselection if they voted against the party’s formal policy, which is opposed to decriminalisation.

Guardian Australia understands the parliamentary vote would have been on a knife-edge if the LNP decided to bind its MPs to that position.

Earlier on Tuesday the premier, Annastacia Palaszczuk, told reporters the bill would “come down to the wire”.

“As a female leader myself I believe this is such a crucial issue for so many people across our state that a conscience vote should be granted,” she said.

Labor has a two-seat majority in the parliament and the support of two cross-benchers. But it’s understood there are a handful of government MPs who maintain reservations about the abortion laws, or whose position is unclear. At least one is considered a “hard no”.

The LNP decision will settle some nerves among pro-choice campaigners, who were disappointed last year by the failure of a private member’s bill, after the LNP announced it was opposed, despite allowing a conscience vote.

The manager of the all-options counselling service, Children by Choice, Daile Kelleher, welcomed the decision.

“Abortion law reform is not a partisan matter,” Kelleher said. “Regardless of where a woman lives in Queensland, or who their local MP is, their life and access to healthcare will be positively affected should this bill pass.

“We’ve talked to MPs from all parties in the Queensland parliament about abortion law reform and we’re hopeful that with the granting of this conscience vote, that the bill will pass.”

If the legislation passes, it would leave New South Wales as the only state in Australia to retain its archaic criminal abortion laws.

In Queensland women face jail terms up to seven years, and doctors up to 14 years, for terminating a pregnancy. The last people charged under the laws were a Cairns couple, who were acquitted in 2010.

There are seven abortion clinics operating in Queensland and anti-abortion groups have argued against reform, citing a lack of prosecutions.

But the criminal laws remain a significant roadblock for women to access services, particularly in regional areas. Public hospitals will not provide surgical abortions, and there is only one clinic outside the state’s urban south-east that operates regularly.

The proposal before parliament next week is similar to laws in Victoria. After 22 weeks permission for a termination must be given by two doctors. A 150-metre safe access zone will block protesters and people who harass women at abortion clinics.

Doctors will be allowed to refuse to perform procedures on moral grounds. They must declare their objection and refer women to another practitioner.