A resolution has been introduced in the US House of Representatives reaffirming support for the Good Friday Agreement.
The bipartisan bill is co-sponsored by Democratic Congressman Thomas Suozzi and Republican Congressman Peter King.
The resolution urges the UK and the EU to ensure that Brexit does not threaten peace on the island of Ireland and strongly opposes the reintroduction of a hard border.
It also insists that any trade agreements between the US and the UK are contingent on meeting the Good Friday Agreement's obligations.
Congressman Suozzi described Ireland as one of the oldest and closest friends of the United States.
"We need to ensure that Brexit and other political challenges don’t threaten the peace process by reintroducing a hard border," he said.
A similar resolution opposing the return of a hard border was introduced in the US House of Representatives in January.
Democratic Congressman Brendan Boyle was behind the move saying that now was the time for the US Congress to make it clear that it stands in strong opposition to a hard border.
A number of senior members of the US Congress have warned that they will oppose any US-UK trade deal that undermines the Good Friday Agreement.
Those who have voiced their opposition include the Speaker of the House Nancy Pelosi, the Senate Minority Leader Chuck Schumer and the Chairman of the House Ways and Means Committee Richard Neal.