There is “more to do” to maintain peace on the island of Ireland and improve Anglo-Irish relations, Irish premier Simon Harris has said.

The Taoiseach was speaking at a British-Irish Council summit on the Isle of Man on Friday.

He said that former taoiseach Bertie Ahern, an architect of the Good Friday Agreement, was “entirely correct” when he said Anglo-Irish relations had become much more fragile and strained since Brexit.

Mr Harris, who became premier in April, said he intends to “invest a significant amount of time” in maintaining Anglo-Irish relations during his tenure.

Northern Ireland Secretary Chris Heaton-Harris, Scottish First Minister John Swinney, and deputy First Minister of Northern Ireland Emma-Little Pengelly, who were also at the summit, said they would like to see the next British prime minister attend the council.

Speaking at a press event on Friday, Mr Harris said he hoped that peace on the island is “a little bit better” than “frosty”, but added “there’s certainly more that we can do and should do”.

The Taoiseach praised “practical projects of co-operation”, citing the Ulster Canal and construction of the Narrow Water Bridge.

“I think forums like the British-Irish Council and the summit that’s taking place here today are absolutely vital because Bertie (Ahern) is entirely correct, as is anybody else who understands that peace and meaningful engagement is based on interpersonal relationships,” Mr Harris said.

“It is really important that we, the custodians of the Good Friday Agreement, now harness the incredible gift that has been given to us.

“Certainly I intend to invest a significant amount of time in those interpersonal relationships.

“I was really delighted to have the opportunity to visit the First and deputy First Minister and Stormont, very grateful to them for hosting me, I look forward to welcoming them to Dublin in the autumn for the next North-South Ministerial Council.”

Ms Little-Pengelly added that “vigilance” on Anglo-Irish relationships is needed and they need to be “tended” to.

“The last number of years was a great demonstration of how those relationships can deteriorate very quickly,” she said.

Mr Heaton-Harris said that the relationships formed at events such as the British-Irish councils are “invaluable” in times of crisis.

He said he believed he had tried to improve relations, which “needs to be constantly cherished and nurtured”.

Noting that the leaders “got to know each other a bit better” at a dinner on Thursday night, he said: “It’s through gatherings like this where, when problems come in a relationship, you have a personal relationship with someone who you can talk to.

“You would be in danger of undervaluing this just by judging it from the communique that came out at the end of the day. We talked about really important issues. I’ve learned so much in my time here.

“We’ve all got quite different politics and quite different remits. But we come together and learn from each other and those interpersonal relationships are unbelievably valuable, especially at times of crisis.”

Asked about whether the next British prime minister should attend the council, Mr Heaton-Harris said “it should be part of the calendar for any British prime minister”, while Mr Swinney “wholeheartedly agreed that it would be beneficial for the UK prime minister to be here on a regular basis”.

Mr Swinney added: “In general, I think we all see our politics is pretty fractured, and the political system is pretty fractured.

“So actually the opportunity that is fostered by this body for political leaders across these islands to come together, and to have courteous and respectful dialogue – which is what we’ve had today, which has always been my experience of the British Council – we frankly can’t have enough of that and we need more of it.”

Mr Harris said that “it merits consideration by the next British prime minister” to attend the next British-Irish Council, particularly as the UK is no longer a member of the European Union.

“So I think it merits consideration as to how do we ensure that there’s plenty of structures in place for that regular dialogue between the British prime minister of the day and the Irish taoiseach of the day, and indeed the administrations are represented here because certainly I would value that and look forward to being in London in July where the UK Government will host the European Political Community meeting and hoping to have early engagement with the British prime minister.”

Ms Little-Pengelly added: “Very many people around the table have very busy jobs and very few opportunities, I think, to actually have those conversations and this provides that opportunity to do so.

“Certainly moving forward I would like to see that prioritised. I think it does show that respect as well to the range of countries and jurisdictions and places across the British Isles and gives us that opportunity to ensure that all of our issues are aired at an appropriate level.”

First Minister Michelle O’Neill, who did not attend the summit due to an illness, took part in the meeting via Zoom.