The cultural celebration has been observed by the Irish as a holiday for more than 1,000 years.

The Irish leader’s White House visit on Friday is a cherished annual tradition. That has never been more true than under Biden, who frequently trumpets his family roots in Ireland and sprinkles quotes from Irish poems through his speeches.

Varadkar’s day will start with breakfast at Vice President Kamala Harris’s residence with “eggs Saint Patrick” on the menu, according to the White House. Varadkar and Biden will then have lunch at the US Capitol, hosted by the Republican Speaker of the House, Kevin McCarthy.

“Ireland and the United States are forever bound together by our people and our passion. Everything between us runs deep,” Biden said.

At the White House, Varadkar – known as the taoiseach – will then present Biden with the traditional shamrock – a sprig of clover representing Ireland. Entertaining the revellers will be Irish pop star Niall Horan, a former member of mega-boy band One Direction, now a singer-songwriter.

The White House is even dyeing its South Lawn fountain green.

The cultural celebration has been observed by the Irish as a holiday for more than 1,000 years.

‘Peace dividend’

There will be weightier issues on the table, however. Biden says he will visit Ireland and the British north soon – possibly to mark the 25th anniversary of the US-brokered Good Friday Agreement, which ended the violent unrest known as the Troubles in Northern Ireland.

The Biden administration watched closely as Britain, Ireland, the European Union and leaders of the British province of Northern Ireland hashed out a compromise – the Windsor Framework – on how to manage cross-border trade now that Britain is out of the EU, which includes Ireland.

Biden and Varadkar will stress their “support for the Belfast/Good Friday Agreement as we approach its 25th anniversary and welcome the recent agreement between the UK and EU on the Windsor Framework as an important step in preserving the agreement’s peace dividend”, the White House said.

Some 32 million Americans – almost 10 percent – claim ancestral roots in Ireland. Given the long history, the fates of the island country and the troubled northern province play outsized roles in US politics.

Biden on Monday said he intends to visit both the Republic of Ireland and Northern Ireland.

If the post-Brexit trade arrangement does get full backing from rival forces in Northern Ireland, that could pave the way for restarting a local power-sharing agreement between pro-British loyalists and the nationalist parties, which want to break away and reunite the province with the Republic of Ireland.