Sinn Féin members have voted in favour of liberalising abortion law in Northern Ireland, saying the procedure should be provided through a GP-led service for a “limited gestational period”.

Party grassroots recognised last month’s referendum decision of voters in Ireland to overturn a constitutional provision that outlawed terminations in most cases.

Q&A What is the law on abortion in Northern Ireland? Show The 1967 Abortion Act which liberalised the law in England, Scotland and Wales never extended to Northern Ireland. The region permitted abortion only if a woman’s life was at risk or if there was a risk of permanent and serious damage to her mental or physical health. The story of Sarah Ewart, who travelled to England for an abortion after being told her baby would not survive outside the womb, galvanised change. The legislation brought in by Westminster, which takes effect on Tuesday, decriminalises abortion. After consultations, the UK government will have to put in place regulations for abortion services by next April; until then, women will be offered free transport and accommodation to access abortion services in England. In England, Scotland and Wales, the limit on abortions except in cases of fatal foetal abnormality or risk to life is 24 weeks. But anti-abortion campaigners in Northern Ireland claim that the change could mean abortion up to 28 weeks.

Delegates at an annual party conference in Belfast decided abortion should also be available where a woman’s life, health or mental health is at risk and in cases of fatal foetal abnormality, where an infant cannot survive.

The party’s vice president, Michelle O’Neill, said: “Sinn Féin refuses to hide. It will address this issue with compassion and will show the leadership that is required.”

New legislation implementing the Irish Republic poll’s overwhelming two-to-one verdict in favour of making the procedure available will be introduced in the new year, the taoiseach has said.

It will make abortion freely available during early pregnancy and in limited circumstances later.

The referendum vote was lauded by proponents as a modernising and compassionate step for women after a fierce debate in which opponents including the Catholic church argued that the unborn baby’s life was sacrosanct.

Sinn Féin is a major force in opposition in the Republic. It is the majority voice of nationalism in Northern Ireland and hopes to make gains in the Republic’s next general election.

Irish society has liberalised in recent years, with public polls in favour of divorce, same-sex marriage and access to terminations.

Pro-choice campaigners from the Republic have turned their focus north of the border after last month’s historic referendum to repeal the Irish state’s restrictive constitutional position on abortion.

MEP Martina Anderson said: “The North is next.”

The debate has intensified since the outcome of the referendum, with the British government resisting renewed calls to step in and legislate in the continuing absence of a power-sharing government in Belfast.