A ban on abortion-including cases involving rape and incest-has been in effect in Northern Ireland since 1861.
The British parliament passed the Northern Ireland (Executive Formation etc) Act 2019 in July, with amendments legalizing abortion and same-sex marriage.
Assembly members will sit for the first time in two and half years later to debate the changes - but it's just a symbolic move and members will have no power to stop them coming into force.
More than 1,000 days since powersharing imploded amid a row over a botched green energy scheme, recent months saw limited progress in efforts to resolve the raft of issues still preventing the DUP and Sinn Fein re-entering government together.
Unionists opposed to abortion reform triggered a special sitting of the Assembly yesterday when more than 30 members (MLAs) signed a petition asking for it to be recalled. But first a speaker had to be elected, which could not be done thanks to a walkout by the Social Democratic and Labour Party (SDLP).More news: Emery reckons Arsenal 'did not deserve to lose' against Sheffield United
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The assembly was briefly restored on Monday, but without support from opposition parties, they were unable to constitute an executive and pass any changes.
Meanwhile, the British government is also now drawing up new regulations to permit gay marriages and same-sex civil partnerships in Northern Ireland.
"This is undemocratic and it's wrong", Bernadette Smyth, director of Precious Life Northern Ireland pro-life campaign group told AFP outside Stormont.
Mary Lou McDonald, leader of Sinn Féin, celebrated the "decriminalisation of women that will take effect from midnight", the BBC reported. The rest of the United Kingdom modified its abortion laws in 1967, but Northern Ireland did not follow suit.
He wrote: "The widespread view that the English "pay for Scotland" goes hand-in-hand with the knowledge that Scots get certain things - free NHS prescriptions and free university education - that are not available in England: in other words, that English taxpayers are paying for the Scots to have things that they don't get themselves".
Signatories of the statement included leaders of the Catholic Church, the Church of Ireland, Methodist Church in Ireland, Presbyterian Church in Ireland, and the Irish Council of Churches.
"It is not lost on the public that the first time the DUP recalled the assembly was yet another attempt to deny a section of our community rights", she added, welcoming the reforms. The UK Government will then begin work on legislation providing access to abortion services in the region by next April.