NI’s Stormont Assembly has sat for the first time in nearly three years after being recalled in a last-ditch attempt to stop abortion law changes.

Unionist parties, who oppose the upcoming liberalisation, triggered the recall with a petition.

Proceedings were delayed, amid reports of legal moves to block the changes.

The politicians who returned were told the assembly “cannot do any business” until a speaker is elected with cross-community backing.

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Shortly after proceedings began, the SDLP walked out, leaving no nationalist representatives in the chamber, which meant no speaker could be elected.

The Democratic Unionist Party (DUP) also walked out, saying this was not the end of the matter.

DUP leader Arlene Foster said it was a “shameful day” and Northern Ireland would have the most “liberal abortion laws anywhere in Europe”.

Northern Ireland has been without a devolved government since January 2017 when the power-sharing parties split.

Abortion laws will change at midnight unless devolution is restored, but the recall is seen as largely symbolic.

Without an executive in place, Stormont cannot affect the laws.

It is unlikely an executive will be established as it needs support from both the unionist and nationalist communities.

Why have politicians been recalled?

Stormont’s power-sharing government collapsed amid a bitter row between the Democratic Unionist Party (DUP) and Sinn Féin.

Several rounds of talks to restore the executive have not succeeded.

MPs in the House of Commons have since passed some key legislation for Northern Ireland.

Speaker Robin Newton said the assembly must as its first business elect a speaker with cross-community support, and could not suspend standing orders first to consider the Defence of the Unborn Child bill proposed by MLAs.

However, the DUP’s Paul Givan said: “The legal opinion of the attorney general is crystal clear… that it is permissible to suspend standing orders to proceed with business.”

In July, MPs voted for legislation which requires the government to liberalise abortion and extend same-sex marriage to Northern Ireland if devolution is not restored by 21 October.

The bid to recall the assembly was proposed by Northern Ireland peer Baroness O’Loan, who opposes any reform of the existing abortion law.

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The petition was signed by 27 DUP assembly members, Ulster Unionist leader Robin Swann and his party colleagues Robbie Butler and Roy Beggs, as well as Traditional Unionist Voice (TUV) leader Jim Allister.

What are the current rules on abortion in NI?

Northern Ireland’s abortion legislation is very different from the law in Great Britain.

The 1967 Abortion Act, which liberalised the rules in England, Scotland and Wales, was never extended to Northern Ireland.

Currently, a termination is only permitted in Northern Ireland if a woman’s life is at risk or if there is a risk of permanent and serious damage to her mental or physical health.

Rape, incest or diagnoses of fatal fetal abnormality – where medics believe that a baby will die before, during or shortly after birth – are not grounds for a legal abortion in Northern Ireland.

What could happen at midnight?

Abortion will be decriminalised if the devolved government is not restored.

The legislation brought in by MPs at Westminster means the UK government will assume responsibility for introducing new regulations to provide greater access to terminations by next April.

Under the act, same sex marriage will become legal in Northern Ireland in January, with the first wedding expected the following month.

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What positions are the NI parties taking?

Sinn Féin said the recall was merely “about playing to the gallery” and its MLAs (members of the legislative assembly) would not go.

The SDLP did not sign the petition either but it has a number of MLAs who are opposed to abortion and are understood to be considering attending the recall sitting in spite of party leader Colum Eastwood branding the move a “stunt”.

The SDLP has described itself as a “pro-life party” but its politicians are free to vote with their conscience on abortion laws.

The DUP MLA Gordon Lyons said his party wanted to return to Stormont to “take decisions on issues that matter to the people of Northern Ireland”.

The Ulster Unionist Party said its 10 MLAs would go to the chamber and it has also proposed a second petition to recall the assembly on Tuesday.

The UUP’s Doug Beattie said his party’s petition was for MLAs to express anger about the collapse of devolution more than 1,000 days ago.

He denied the UUP was engaging in “stunt politics” of its own and said something needed to be done given the absence of formal talks to restore power-sharing at Stormont.

Alliance Party leader Naomi Long said none of her party’s MLAs would be attending and she described the recall as a “cynical political stunt”.

“The intention of this recall is not to block abortion law and equal marriage but to create the illusion the DUP are trying to do so,” she added.

The Green Party leader Clare Bailey said it was a “shameful pantomime” and that she would not enter the chamber.