- The US House Speaker on Wednesday repeated previous warnings that Congress will not allow President Trump to sign a trade deal with the UK if Brexit has disrupted the seamless Irish border.
- If Brexit undermines the Good Friday accord, there will be no chance of a U.S.-U.K. trade agreement passing the Congress," Pelosi said in a statement.
- Prime Minister Boris Johnson has prioritised a trade agreement with the US once the UK has left the European Union. Trump has promised a comprehensive and deep trade deal.
- However, last week former US treasury secretary Larry Summers said the UK would be "desperate" in trade talks and that Trump would "strike the hardest bargain."
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There is "no chance" of a free trade deal between the United Kingdom and the United States passing Congress if Brexit undermines the Good Friday Agreement or the open Irish border, US House Speaker Nancy Pelosi warned on Wednesday.
Trump's National Security adviser John Bolton insisted this week that Britain would be first in line for a trade deal with the US after Brexit, and said that the US "enthusiastically" supports Britain leaving the EU without a deal.
However, Pelosi warned that Congress will not approve any post-Brexit trade deal with the UK if Brexit disrupts the status quo on the island of Ireland, as a no-deal Brexit would likely do.
Pelosi in a new statement said the Good Friday Agreement which underpins the relationship between Northern Ireland and the Republic will be "fiercely defended" in Washington by both the Democrats and the Republicans.
Pelosi said: "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."
"The Good Friday Agreement serves as the bedrock of peace in Northern Ireland and as 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.
She added: "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.
"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."
Brexit-backing UK politicians including Prime Minister Boris Johnson argue that a free-trade deal with the US will be one of the biggest benefits of leaving the EU. Trump has promised a deal that will be unprecedented in scope.
However, UK-based trade experts have said that a UK-US trade deal will likely take years to negotiate, and that US negotiators will demand access to areas of UK industry that British politicians and the public would find unacceptable.
An example of this is in agriculture. There is concern that US companies could flood the UK market with cheap goods that would undercut British businesses and reduce the standards of goods sold in the UK.
Last week Larry Summers, a former US treasury secretary, warned that the UK will be "desperate" and without "leverage" in talks with the US, meaning Trump will "strike the hardest bargain."
"The last thing you do is quit a job before you look for your new one," Summers told BBC radio.
"In the same way, establishing absolutely that as a matter of sacred principle you're leaving Europe has to be the worst way to give you leverage with any new potential partners."
Summers added: "Britain has much less to give than Europe as a whole did, therefore less reason for the United States to make concessions. You make more concessions dealing with a wealthy man than you do dealing with a poor man."