STORMONT parties should currently "focus on governing" rather than the future of the border, former secretary of state Julian Smith has said.
The Conservative MP said parties can "have a debate on constitutional issues" but added that much work can be done "on the north-south bodies, on climate change, on infrastructure".
Mr Smith was Northern Ireland secretary for just 204 days but helped to secure a deal restoring devolution in January following a three-year hiatus.
British prime minister Boris Johnson replaced him five weeks later with the current secretary of state, Brandon Lewis.
In an interview with BBC Radio Ulster's Talkback programme, Mr Smith said he remains "committed long-term to doing anything that's needed to assist" Northern Ireland.
"I think the biggest message and the biggest thing that I hope will happen is that, over and above the constitutional debates, in the back of every politician's mind is that they stood on the sidelines for three years and didn't lead despite being paid and service the interests of the people of Northern Ireland," he said.
"I think if all parties focus on governing now –yes, have a debate on constitutional issues and obviously there are big topics there – but there's a lot that can be done on the north-south bodies, on climate change, on infrastructure."
He added: "I was really struck when we did the Stormont deal, people were literally coming up to me in the street and just thanking me for getting it back up and running.
"That was because, not that they didn't have views on the constitution, but at the moment the focus needs to be on getting stuff done, whether it's education, healthcare, whatever."
Mr Smith said Northern Ireland has some "extremely talented" assembly members.
He said the importance of devolution had been shown by how Stormont has handled the coronavirus pandemic.
"If we'd gone in to either no deal [Brexit] last year without some form of governance or this pandemic without a government we would have had major issues," he said.
"So I think the biggest thing is to applaud all those political leaders for getting through that period."
Mr Smith recalled how the day he was appointed Northern Ireland secretary, he'd had "far too many beers" after going to the pub upon losing his job as Conservative chief whip.
He said he was honoured to take on the new role, and restoring the executive was his first priority.
"Those early weeks were frustrating because the political parties were really not engaging and there was ebbing and flowing between Sinn Féin and the DUP in their levels of enthusiasm," he said.
Mr Smith added that he was not bitter about being replaced as secretary of state.
"I'm really committed long-term to doing anything that's needed to assist a part of the UK that has been through the most horrendous times, that when I was a child was on the television every night," he said.
"I was then given this opportunity to help as secretary of state and I will continue to help in the best way I can.
"What potential it has, the young people, the hope for the future – the need is to really focus on what matters and that is about people, understanding people, trusting people, working with people."
Responding to the comments, Sinn Féin MP Francie Molloy accused the British government of acting in bad faith.
“It is the legitimate and democratic right of the people of Ireland to seek and work towards Irish unity. That right is enshrined in the Good Friday Agreement," he said.
“Comments from a former Tory minister calling on nationalists and republicans to set aside that legitimate aspiration is a further indication of the bad faith of the British government. It is yet another attempt to abandon its responsibilities and legal obligations under the agreement."