House Speaker Nancy Pelosi issued a warning to the United Kingdom Wednesday amid talks of a free trade deal with the US after Britain departs the European Union.

The top-ranking House Democrat issued a statement reiterating her opposition to any free trade agreement that disrupts the Good Friday Agreement, calling it “the bedrock of peace in Northern Ireland” and “a beacon of hope for the entire world.”

“After centuries of conflict and bloodshed, the world has witnessed a miracle of reconciliation and progress made possible because of this transformative accord,” the press release read.

The Good Friday Agreement was approved in 1998, ending decades of bloodshed between Ireland and Northern Ireland.

The two nations share a border, though Northern Ireland is a part of the UK while Ireland is part of the EU.

Brexit negotiators have struggled with making a deal that doesn’t violate the accord or create a situation where a hard border or no border is placed between the two countries.

Critics of Brexit proposals have cautioned that any deals which alter the Good Friday Agreement could put peace between the two countries at risk.

The House speaker referenced the importance of maintained peace in the region in her statement.

“If Brexit undermines the Good Friday accord, there will be no chance of a U.S.-U.K. trade agreement passing the Congress. The peace of the Good Friday Agreement is treasured by the American people and will be fiercely defended on a bicameral and bipartisan basis in the United States Congress.”

Pelosi’s comments come in response to comments from national security adviser John Bolton, who told British reporters Tuesday that Britain would be at the “front of the trade queue” for a new trade agreement with the US if and when it leaves the EU.

When asked if the US would maintain the same eagerness if the UK is forced to take a no-deal Brexit, Bolton didn’t hesitate, saying, “If that’s the decision of the British government we will support it enthusiastically, and that’s what I’m trying to convey. We’re with you, we’re with you.”

Pelosi, however, set a different tone with her statement.

“Whatever form it takes, Brexit cannot be allowed to imperil the Good Friday Agreement, including the seamless border between the Irish Republic and Northern Ireland, especially now, as the first generation born into the hope of Good Friday 21 years ago comes into adulthood.

“We cannot go back.”