By Andrea Shalal and Trevor Hunnicutt

WASHINGTON (Reuters) – U.S. President Joe Biden on Wednesday underscored his strong commitment to the landmark 1998 Good Friday peace agreement and the need to maintain the political and economic stability of Northern Ireland.

“We strongly support that, and think it’s critically important to be maintained,” Biden said at the start of a virtual meeting with Irish Prime Minister Micheál Martin on St. Patrick’s Day. “The political and economic stability of Northern Ireland is very much in the interest of all our people.”

Biden and Martin pledged to expand ties between the two close allies, including on issues such as climate change, combating the coronavirus pandemic, and cancer research.

Martin said he looked forward to visiting Washington and hoped Biden would be able to visit Ireland once it was safe.

The Irish leader thanked Biden for his “unwavering support” of the Good Friday Agreement, adding, “It has meant a lot. And it has mattered.”

“With a new trading relationship now in place between the European Union and the United Kingdom, and a protocol that protects peace and avoids a hard border on this island, I want to move forward with a positive relationship with the United Kingdom,” Martin said. “That means standing by what has been agreed and working together to make a success of it.”

A senior U.S. official told reporters before the meeting that the Biden administration viewed a British-EU rift over the movement of goods to Northern Ireland as a trade issue, and would not take sides on the matter.

Martin also met virtually with U.S. Vice President Kamala Harris, who underscored what she called America’s “steadfast and strong” commitment to Ireland.

“In the midst of global freedoms being in decline, our nations remain close because we are committed to democracy,” Harris said in her ceremonial office, which was adorned with a large shamrock-type plant in honor of St. Patrick’s Day.

Biden, an Irish-American, said the White House would be illuminated in green later Wednesday to “celebrate the deep, deep affection” Americans had for Ireland. Fountains at the White House also ran green, continuing a tradition that dates back to the administration of former President Barack Obama.

“The key objective is of course to deepen our relationship,” Martin told MSNBC earlier. “In President Biden, we have the most Irish-American president since John F. Kennedy, and his election was greeted with great affection and warmth in Ireland.”

The meeting came amid simmering disputes related to the implementation of agreements put into place as the UK exited the EU, including the Northern Ireland protocol, which governs the movement of goods into the British-ruled province.

The dispute has raised tensions in the region, more than two decades after the 1998 accord that largely ended three decades of violence between mostly Protestant unionists, who want Northern Ireland to stay in the UK, and mostly Roman Catholic nationalists seeking to unite the Irish Republic and Northern Ireland.

Biden has long expressed firm support for the Good Friday Agreement.

The senior U.S. official said Washington welcomed provisions in both the EU-UK Trade and cooperation agreements, as well as the Northern Ireland protocol, which it believed would protect the gains of the peace agreement.

The United States would not “take sides” in the dispute over implementation of the protocol, the official said. “We view that as a trade issue to be resolved between the UK and the EU, and hope that both sides are able to return to the table and discuss the implementation of the agreement.”

Martin has said Ireland, an EU member, is counting on U.S. support to help maintain the political stability of Northern Ireland.

Earlier this month, Northern Irish loyalist paramilitary groups said they were temporarily withdrawing support for the 1998 peace agreement due to concerns over the Brexit deal.

The groups expressed concern about a disruption to trade between Britain and Northern Ireland and said they believed that Britain, Ireland and the EU had breached their commitments to the peace deal.

No decision has been made on the U.S. appointment of a special envoy to deal with Northern Ireland, the U.S. official said.

The virtual meeting with Martin is the first bilateral event with Ireland hosted by Biden, who attended a St. Patrick’s Day Mass at his church in Delaware before returning to Washington. Biden is expected to make a trip to Ireland as soon as this summer.

Martin also participated virtually in the annual U.S. congressional luncheon marking Ireland’s national day and the close ties between the two countries.

(Reporting by Andrea Shalal and Trevor Hunnicutt; Additional reporting by Steve Holland in Washington and Conor Humphries in Dublin; Editing by Peter Cooney and Rosalba O’Brien)