US House of Representatives speaker Nancy Pelosi will meet Taoiseach Leo Varadkar in Dublin on Tuesday.
Ms Pelosi is part of a delegation of high-ranking US politicians on a two-day fact-finding mission to Ireland.
The congressional group will meet with Mr Varadkar at Government Buildings on Tuesday afternoon, following a lunch hosted by Tanaiste and Foreign Affairs Minister Simon Coveney.
On Wednesday Ms Pelosi will address TDs, senators and former politicians in the Dail chamber.
Later that day the group will meet President Micheal D Higgins and the Taoiseach will host a dinner at Dublin Castle in honour of the delegation.
The delegation includes several members of the Friends of Ireland caucus, including Congressman Richie Neal.
The US politicians will also visit Northern Ireland.
On Monday Ms Pelosi said there would be no chance of a US-UK trade deal if there was any weakening of the Good Friday Agreement.
Astonishing 70% of Irish adults would vote for a United Ireland
Speaking at the London School of Economics, she said that the accord was a model that could not be bargained away in another agreement.
Ms Pelosi is the third most powerful politician in the United States.
Speaking ahead of the visit Mr Varadkar said: "It's an honour to welcome the delegation from the US Congress to Ireland.
"This visit is more evidence of the deep and historic ties between our two countries and is a good opportunity to further deepen US-Ireland bilateral relations.
"We will discuss a range of issues including trade, visas, immigration and Brexit."
