US President Joe Biden met virtually with Irish Taoiseach (prime minister) Micheal Martin on Wednesday to mark St Patrick's Day and reaffirm his commitment to the Good Friday Agreement.
The meeting was Biden's third with a foreign leader since he took office eight weeks ago.
It included the presentation of an engraved bowl of shamrock which was sent on to Washington - continuing a tradition that began in 1952.
The White House said Biden would also drop in on Vice President Kamala Harris' meeting with Northern Ireland's First Minister Arlene Foster and Deputy First Minister Michelle O'Neill in a show of support for the Good Friday Agreement.
Signed in 1998, the Good Friday Agreement helped end sectarian violence that had raged for three decades over the issue of Northern Ireland unifying with Ireland or remaining part of the UK.
Biden told Martin that it is "critically important" that the Good Friday Agreement be maintained.
The UK's 1 January exit from the EU has created new tensions over trade and travel at the Irish border.
EU authorities on Monday initiated legal action against the British government for violating the Brexit agreement's Northern Ireland Protocol, which was designed to keep the border open and protect the peace process in Northern Ireland.
That sparked an angry response from Northern Ireland's Democratic Unionist Party, which said the EU was more interested in protecting its internal market than the peace process.
The party, which wants to maintain ties to the UK, has criticised the protocol for treating the province differently from the rest of the country.
Watch Euronews Tonight's interview with Tommy Graham, editor of History Ireland in the video player above on Saint Patrick's Day.