Political leaders in Northern Ireland, Ireland and Great Britain need to find a “practical, workable” way forward to restore powersharing at Stormont, Senator George Mitchell has said.

Mr Mitchell, one of the architects of the Good Friday Agreement, said any solution that is found to the current impasse will not be perfect and will also not be permanent.

The former US special envoy for Northern Ireland made the remarks just hours ahead of a deadline for fresh elections to be called in Northern Ireland if devolved government is not restored in time.

The Stormont Assembly failed to elect a new speaker during a recalled session on Thursday afternoon.

A six-month legislative timeframe to form an administration expires just after midnight early on Friday.

If no ministerial executive is in place by then, the UK Government assumes a legal responsibility to call another election.

Mr Mitchell told an Irish parliamentary committee nearly 25 years after the signing of the Good Friday Agreement that the people of Northern Ireland continue “to wrestle with their doubts, their differences, their disagreements”.

“That is not and should not be a surprise,” he said.

“No society is free of differences and disagreements. But unlike in the times prior to the agreement, they are trying to resolve their differences, through democratic and peaceful means, not through violence.

“Imperfectly, to be sure, slowly trying to work forward with occasional steps backward.

“But with the support of the governments and the people of Ireland and the United Kingdom we hope that they will, and with support of people of goodwill all around the world, they must be encouraged to resolve their differences peacefully.

“The solutions will not be perfection or permanent. So it is for the current leaders of Northern Ireland, Ireland and of the United Kingdom, to find practical, workable solutions and answers to the current problems to preserve the peace to further freedom and opportunity for their people.”

He told committee members that while the agreement was a “great accomplishment” it did not, in itself and by itself, permanently resolve all the difficult issues confronting the people of Northern Ireland that “continue to this day”.

The DUP has refused to engage with the devolved institutions in Belfast in the wake of May’s Assembly election, meaning it has not been possible to form an executive.

The party’s boycott is part of a campaign of opposition to Brexit’s Northern Ireland Protocol and the DUP says it will not return to powersharing until decisive action is taken to remove the protocol’s economic barriers on trade between Great Britain and Northern Ireland.

Mr Mitchell said political leaders should not worry about finding a solution that will last forever.

“Even if this were magically solved, in the next 60 days, let’s say, and the government is restored, no-one should think that that’s a perfect, permanent solution,” Mr Mitchell said.

“It is meeting the current challenges but life has changed. Life has changed for each individual human being, for each society, for each government, for each nation.

“And I think it’s a truism that, in human affairs, a solution to every problem contains within itself the seeds of a new problem.”

He added: “I think the challenge for Northern Ireland, for the political leaders, now is figure out a way, a practical, workable way to get this process back on track, to get the Assembly functioning, the first and deputy ministers in place and deal with practical day-to-day problems that people in Northern Ireland have, and don’t worry about doing, creating something that will last for all time, forever,” he added.

“It’s not going to. It’s going to be challenged again, the following year. So I think it’s more an attitude than it is a particular issue.”

Mr Mitchell also told the joint committee on the Implementation of the Good Friday Agreement that if the people of Northern Ireland have a fault it is that they are “too self-critical”.

“Self-criticism is a good thing,” he told TDs and senators. “But there’s a great deal of self-criticism I know of now that I think it’s unwarranted.”

He added that people need to move beyond the “negatives” that have accumulated over time.

He apologised to the committee for not be able to attend the sitting in Dublin in person, telling members that he had been diagnosed with acute leukemia two years ago which has severely curtailed his travel and public appearances.