US President Joe Biden urged Northern Ireland to “sustain the peace” on Wednesday in a half-day foray into the region's politics marking 25 years since the Good Friday Agreement.
Mr Biden said an economic boom fuelled by American investment was on the cards “if things continue to move in the right direction”.
He spoke at an Ulster University campus after short meetings with UK Prime Minister Rishi Sunak and leaders of the major Northern Irish parties.
Amid a prolonged political stalemate casting a cloud over the anniversary, Mr Biden made an appeal for parties to return to power-sharing.
“It’s up to us to keep this going. To keep building on the work that has been done every day for the last 25 years,” Mr Biden said.
“To sustain the peace, unleash this incredible economic opportunity which is just beginning.”
The US and UK rejected claims that the brief stay in Belfast constituted a snub, with Mr Biden departing in the afternoon for a three-day homecoming in the Republic of Ireland.
Amid warnings of gales and thunderstorms on the island, Mr Biden was to be driven to an ancestral family home in Carlingford rather than taking the helicopter Marine One. The weather had held up in Belfast with largely clear skies on Wednesday morning.
The visit to Belfast passed off peacefully after unrest involving petrol bombs in Derry had marred Monday’s anniversary. A moderate crowd gathered behind police barricades to watch Mr Biden's motorcade leave the Grand Central Hotel.
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The 1998 Good Friday Agreement — brokered with the help of US president Bill Clinton— mostly ended the 30-year bloodshed in Northern Ireland known as The Troubles.
It created a system of power-sharing between Catholic pro-Irish republicans and Protestant pro-UK unionists and cooled the temperature by mandating arms reductions on both sides.
However, the power-sharing assembly has been in limbo for months with the Democratic Unionist Party refusing to share power since last year.
White House officials downplayed suggestions Mr Biden would look to twist unionist arms during his meetings with party leaders.
Biden hopes Northern Ireland parties will restore power-sharing government
In his public remarks, Mr Biden said a recent Brexit agreement that sought to address DUP grievances would encourage investment in Northern Ireland.
"There are scores of major American corporations wanting to come here, wanting to invest," he said.
However, DUP leader Jeffrey Donaldson said Mr Biden’s intervention did not change the political dynamic at Stormont.
"We believe the [UK] government needs to go further in terms of protecting Northern Ireland's place within the United Kingdom," Mr Donaldson said.
Aides to Mr Biden rejected accusations that the President, a Catholic Irish-American, was anti-British or appearing to favour Irish nationalism with the lopsided schedule of his trip.
“The track record of the President shows that he’s not anti-British,” said Amanda Sloat, a director for Europe on Mr Biden's National Security Council.
On the question of Irish unity, she said: “The President is a strong supporter of the Good Friday Agreement, and the Good Friday Agreement includes mechanisms by which the people of Northern Ireland can make that decision for themselves.”
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Downing Street rejected claims that the hotel meeting with Mr Sunak amounted to little more than a “bi-latte,” rather than a formal bilateral meeting. The White House said they drank tea during their talks.
Mr Sunak told reporters that “the relationship is in great shape”.
“We’re very close partners and allies, we co-operate on a range of things, whether that’s supporting Ukraine or economic security,” he said.
Mr Sunak's office said the two leaders “expressed their sincere hope” that power-sharing would soon be restored.
They agreed that the anniversary was “a moment to celebrate the progress that Northern Ireland has made” and to “recommit to building an even brighter future”, according to Downing Street.
The White House's announcement that first lady Jill Biden, not the President, will attend the coronation of King Charles III has also raised eyebrows in London.
In his speech, Mr Biden saluted young people driving an economic revival in Northern Ireland having grown up during the years of relative peace.
It came after police said young children were involved in republican unrest in Derry that overshadowed the 25th anniversary.
Four pipe bombs were discovered in a cemetery hours before Mr Biden landed on Tuesday, in what police called a “sinister and worrying development”.
Police vans were attacked with petrol bombs in Derry a day earlier in a reminder of the continued threat of violence.
In the Republic of Ireland, Mr Biden was to visit an area where his great-grandfather James Finnegan, born in 1840, lived before emigrating to America.
Mr Biden’s sister Valerie Biden Owens and his son Hunter Biden are joining him for the trip.
