The US President's told a room full of representatives from Ireland, Northern Ireland and America in Washington to 'march forward together'.
Politicians from across Ireland are visiting the US ahead of St Patrick's Day.
It's the first time Stormont's First and Deputy First Ministers have attended together in eight years, and follows the restoration of Stormont in January.
At a lunch in Washington, Taoiseach Leo Varadkar said he was grateful to America for its role in the peace process.
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