People will be “absolutely aghast” that unionists were focused on a centenary stone in the same week the Assembly failed to elect a speaker to pass life-saving legislation, the Sinn Fein vice-president has said.

While devolved government at Stormont remains unable to function, a decision was made by the Assembly Commission to allow the placing of a ceremonial stone to mark Northern Ireland’s centenary.

It follows a row between the parties in 2021 – the year of the region’s centenary – when Sinn Fein opposed the proposal.

Sinn Fein MLA John O’Dowd vetoed the initial request at the Assembly Commission, a body which continues to function to manage Stormont’s property, staff and services.

But Mr O’Dowd stepped away from his role on the Assembly Commission in 2022 after he was appointed Infrastructure Minister.

Sinn Fein were not able to nominate a replacement because the Assembly has been paralysed by DUP protest action over Brexit’s Northern Ireland Protocol.

The commission currently consists of representatives of four of the five largest parties at Stormont – DUP, UUP, Alliance and SDLP.

A spokesperson for the commission said it had met on Monday and there had been consensus among the four members who hold office to agree the proposal.

They added: “Therefore, officials will now be working through the process required to give effect to the decision.”

Michelle O’Neill said she believed the public would be “absolutely aghast” at that happening during efforts to elect a speaker to pass Daithi’s Law.

The new organ donation legislation – which would see an opt-out system adopted in Northern Ireland – was passed by the Assembly last year, but requires enabling legislation to be enacted.

An attempt to recall the Assembly to pass this failed on Tuesday when the DUP again refused to back the nomination of a speaker.

This was the sixth failed attempt to recall the Assembly.

The DUP has consistently maintained it will not participate in devolved government until its concerns around the protocol are addressed.

Ms O’Neill expressed incredulity that the decision about the stone was made on Monday, on the eve of the attempt to revive the Assembly.

Speaking to media in Coalisland, Co Tyrone, on Wednesday she added: “I think the public will make their own mind up on that.”

Earlier in a joint statement, DUP leader Sir Jeffrey Donaldson, UUP leader Doug Beattie and TUV leader Jim Allister welcomed the move to permit the stone.

“We are pleased that, though belatedly, the Northern Ireland centenary will be marked permanently in the curtilage of Parliament Buildings by a centenary stone,” they said.

“It was over two years ago that the Assembly Commission refused a collective request from the leaderships of our parties to erect such a commemorative stone, causing great hurt to the unionist community.

“Earlier this month, we renewed our request to the Assembly Commission. This time they have given approval, which is most welcome.”

The unionist leaders said the stone, which would be in the shape of a map of Northern Ireland, would be mounted on a Portland stone plinth, on a raised area to the west of Parliament Buildings.

“The stone will be paid for by unionist MLAs and therefore will not cost the public purse,” they said.

“Our only regret is that Sinn Fein blocked the proposal when first made, but this time they were unable to do so.

“We will give details in due course of the public unveiling of the stone.”

In 2021, Sinn Fein said it vetoed the proposal because the stone had been “designed and commissioned by representatives of one tradition” and accused unionists of failing to consult with other parties about their plan.