Thousands take part in a protest march in Belfast, calling for the legalisation of same-sex marriage. (John Rooney/Pacific Press/LightRocket/ Getty)

Same-sex marriage will be legalised in Northern Ireland at midnight tonight if a minority of DUP and UUP members are unable to block it.

Northern Ireland is the only part of the UK where abortion and same-sex marriage are not legalised.

The province has not had a working government since the Northern Ireland Assembly, Stormont, collapsed in January 2017. In two historic votes on on July 9, MPs voted overwhelmingly in favour of changing the laws on abortion and same-sex marriage on October 21 if the devolved government has not been re-established by that date.

Today, on the eve of that deadline, Stormont will sit for the first time in two and a half years after a petition of recall received the required 30 signatures – all from unionist members.

It’s thought to be a largely symbolic move in protest against same-sex marriage and abortion, as only one-third of MLAs are set to attend and legislative functions can’t be performed without a ministerial executive in place.

The left-wing party Sinn Fein has made clear it will not turn up to the sitting, indicating that the rift between the DUP and Sinn Fein is as wide as ever.

Rights for LBGT+ people & women cannot & will not be vetoed tomorrow Sinn Féin will not allow this to happen The DUP will pretend they are trying to set up an Executive – a cynical stunt Sinn Féin remain ready to establish an Executive on basis of equality, rights & integrity — Michelle O’Neill (@moneillsf) October 20, 2019

Without significant cross-party involvement the Assembly recall is nothing more than a “stunt” and a “circus”, according to Sinn Fein vice president Michelle O’Neill.

On Friday, she dismissed any MLA taking part in the sitting as a “clown” adding: “Arlene Foster is involved in stunt politics, she is going to lead her team into the Assembly that is not sitting on Monday, they are going to discuss issues that they can do nothing about.”

Proceedings in the Assembly chamber are due to begin at noon. Assuming that a government is unable to be reformed, same-sex marriage will be legalised by midnight, with the first marriages taking place on February 14, 2020 – Valentine’s Day.

“Once we get past that October 22 deadline we will deliver it full stop,” said Lord Ian Duncan, Northern Ireland Office Parliamentary Under Secretary of State, speaking to PinkNews last month.

Along with other same-sex marriage advocates, he has been working to change the legal code ahead of time, so that same-sex couples in Northern Ireland will enjoy the same rights as those elsewhere in the UK.

“What we have to ensure is that wherever the law mentions ‘husband and wife’ and ‘man and woman’ it has to be corrected to reflect the change,” he said.

“We’re working to identify all areas where legacy language exists. The legislation impacted by this covers pensions, benefits and so on.

“We want to make sure that on that date in January, we don’t miss something. So we’re working assiduously to ensure that absolute legal certainty is granted, exactly as you would be if you were marrying as a heterosexual couple.”