Chris Heaton-Harris has said powersharing is “the surest way” to secure Northern Ireland’s place in the union, as he said real leadership is about having the courage to say “yes”.

The Northern Ireland Secretary said those who are proud of Northern Ireland’s place in the Union “should put the Union first” and restore the devolved institutions.

Mr Heaton-Harris was speaking at a three-day conference at Queen’s University to mark the 25th anniversary of the Good Friday Agreement at a time when the Stormont Assembly remains effectively collapsed.

Tanaiste Micheal Martin (left) and Northern Ireland Secretary Chris Heaton-Harris (Niall Carson/PA)

The DUP has said it will not participate in the Assembly until its concerns around the Northern Ireland Protocol are addressed.

The party has expressed concerns over the Windsor Framework, which the UK agreed with the EU earlier this year in an attempt to persuade the DUP to call off its Assembly boycott.

Mr Heaton-Harris said the narrative that unionism was not served well by the Good Friday Agreement is “wrong”.

Speaking in the Whitla Hall at Queen’s, he said he has been struck by a narrative that has “become louder in recent years – a narrative that the Agreement struck in 1998 did not achieve great things for unionism”.

He said: “That it was somehow all-out wins for nationalism. That narrative is wrong. And all of those, all of us who support the Agreement, must be vocal in countering it.

Sir Jeffrey Donaldson (Liam McBurney/PA)

“Today, the principle of consent is so often taken for granted but it was an important and hard-won guarantee that settled Northern Ireland to remain as part of the United Kingdom.”

Mr Heaton-Harris said the “simple reality” is that people tend to change the status quo only when the status quo is not working, or people simply stop making the case for it.

“Devolved powersharing institutions created a status quo that those of us who value Northern Ireland’s place in the Union can robustly and successfully promote and celebrate.

“So let no-one tell you that powersharing is at any way at odds with unionism.

“Instead it is the surest way by which Northern Ireland’s place in the union can be secured,” he said, in comments that prompted applause from the crowd.

Mr Heaton-Harris said the people of Northern Ireland are demanding better, more responsive public services, greater economic prosperity and a brighter future for their children.

“The biggest threat to Northern Ireland’s place in the Union is failing to deliver on these priorities.

“I make no apologies for being proud of Northern Ireland’s place in the Union and for wanting it to continue.

Sir Tony Blair, former US president Bill Clinton and former taoiseach Bertie Ahern (Niall Carson/PA)

“Others who share that view should put the Union first, restore the devolved institutions and get on with the job of delivering for the people of Northern Ireland,” he said.

Mr Heaton-Harris said real leadership is about having the courage to say “yes”, telling the crowd: “Like David Trimble, David Ervine before in 1998, Dr Paisley in 2006, real leadership is about knowing when to say yes and having the courage to do so.”

Meanwhile, Tanaiste Micheal Martin also called for the return of the Stormont executive, saying the UK Government “stretched themselves” to achieve the Windsor Framework.

“The past few years, with the practicalities of Brexit, have been turbulent for Northern Ireland, and for these islands,” he said.

“The European Commission and the UK Government stretched themselves in recent months to reach an accommodation that works for Northern Ireland.

“I know that turbulence will take some time to settle, that parties need to pause and reflect internally on next steps.

Tanaiste Micheal Martin (Niall Carson/PA)

“But I urge all elected officials to take their seats in the assembly and the executive and get to work on the questions of everyday life that matter to the people of Northern Ireland, including healthcare, education, policing, regional imbalances and much more.”

Mr Martin also called on the Northern Ireland parties to recapture the spirit of the Good Friday Agreement.

“Let us recapture and renew that generous spirit of the Agreement,” he said.

“Let’s make the effort again to see this place and see what has happened through the eyes of those we don’t agree with.

“When we do, I am certain that we will recognise the potential of the opportunity before us.

“The potential of a decade of investment and renewal, the potential of our young people when they are given an education and the chance to thrive, potential that we dare not squander.”

The event at the Queen’s University Belfast has seen the participation of major political divs including former US president Bill Clinton, former prime minister Tony Blair and former taoiseach Bertie Ahern.

On Tuesday, the Agreement25 Conference will also see participation in a panel event by European Commission vice-president Maros Sefcovic, and a panel event with Northern Ireland political leaders.

Meanwhile, Mr Clinton is set to give a speech at the Guildhall in Londonderry.

Prime Minister Rishi Sunak is scheduled to make a closing address to the conference on Wednesday ahead of a dinner event which former prime ministers Boris Johnson and Liz Truss are expected to attend.