PRESIDENT Joe Biden is expected to highlight the achievements gained since the 1998 Good Friday Agreement when he makes a keynote address in Belfast later today.
The president will officially open Ulster University's new Belfast campus, in what is the sole public engagement of his visit to Northern Ireland.
Mr Biden landed in the north last night on Air Force One and was greeted on arrival by British Prime Minister Rishi Sunak.
The two leaders were due to meet for 30 minutes over coffee ahead of the president's engagement at Ulster University early in the afternoon, amid tight security.
The pair are not expected to discuss a post-Brexit free trade agreement during their meeting, it has been indicated.
In a briefing to journalists this morning, Amanda Sloat, senior director for Europe at the US National Security Council, said the focus of the meeting will be Northern Ireland, as well as touching on the war in Ukraine.
Read more:Live - US President Joe Biden's visit to Belfast
"I don't anticipate that the two leaders are going to be talking about a free trade agreement on this trip ... I think their conversation is going to focus primarily on the situation in Northern Ireland given that that's where they're meeting, as well as the chance to touch base on Ukraine and some other issues," she said.
The president's first in-office visit to the north coincides with events to mark the 25th anniversary of the Good Friday Agreement.
However, the celebrations have been overshadowed by the political deadlock caused by the DUP's boycott of the Stormont institutions.
There have also been warnings of possible attacks by dissident republicans.
In his speech at Ulster University President Biden is expected to urge the parties to seek a resolution to the current impasse and to embrace the economic opportunities offered by February's EU-UK deal which revised the Northern Ireland Protocol.
Asked on Tuesday what his top priority for the trip was, the president said: "Make sure the Irish accords and the Windsor agreement stay in place; keep the peace. That's the main thing."
Commenting on the presidential visit, which on Wednesday afternoon sees President Biden travel to the Republic, Sinn Féin president Mary Lou McDonald said there was a need to "stop this sense of limbo" in relation to the Stormont institutions.
She told Sky News the president was likely to "reflect on the great success of the last 25 years building peace".
"I think he will obviously reflect also on the huge role of the United States of America in that," she said.
"I have no doubt that he perhaps shares certainly my disappointment, Sinn Féin's disappointment that on this occasion marking 25 years of the peace accord, that the institutions aren't up and running, that we still don't have government in Belfast and that the DUP continues its boycott."
