Brendan Boyle in 2018.Getty

Pennsylvania Representative Brendan Boyle has warned the United Kingdom that there will be no UK-US trade deal if the British Government backtracks on the Brexit Withdrawal Agreement and violates the Good Friday Agreement in the process. 

Boyle, whose father is from Donegal, launched an impassioned defense of the Good Friday Agreement on Channel 4 News, arguing that erecting border checks between Ireland and Northern Ireland could impact the fragile peace built over the last two decades in the region. 

"I don't know why anyone in the world would want to bring back this issue," Boyle said. "It is truly staggering.

"If you need to create checks there [between Ireland and Northern Ireland] and certain infrastructure to support that, that can have a destabilizing effect. We saw it before in the middle part of the 20th century when those border checks were erected in the first place." 

The British Government had agreed to a Withdrawal Agreement in January that guaranteed no border checks between Ireland and Northern Ireland, but the Government appeared to go back on its word by introducing the Internal Market Bill earlier this month. 

The bill seeks to protect trade between England, Scotland, Wales, and Northern Ireland and would likely result in the installation of customs checks between Ireland and Northern Ireland, violating the Good Friday Agreement. 

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When host Matt Frei put it to Boyle that the British Government had claimed it introduced the bill to defend the Good Friday Agreement, Boyle described it as sheer nonsense. 

"I give them credit for saying that with a straight face, that is a real achievement," he said. 

Boyle, who is a member of the Ways and Means Committee responsible for US foreign trade deals, told Channel 4 that there would be no chance of a trade deal between the US and the UK post-Brexit if the UK violated the Good Friday Agreement. 

He said that he traveled to London with House Speaker Nancy Pelosi and several others 18 months ago to discuss a potential trade deal with British negotiators and warned his counterparts then that there would be no deal if the Good Friday Agreement was impacted.

The US is a guarantor of the Good Friday Agreement, Boyle said, and it would do everything it could to protect it throughout the remainder of the Brexit process. 

He said it would be truly tragic if the UK violated the agreement and that there would be no US-UK trade agreement "period" if they did. 

Boyle said that the issue was bi-partisan in the United States and that both Republicans and Democrats took a similar stance on the issue. 

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