Ms Pelosi has warned the UK that there will be "absolutely no chance" of a trade deal with the US passing Congress should the Government override the Brexit withdrawal agreement signed by Prime Minister Boris Johnson. The Speaker of the House of Representatives said Brexit could not be allowed to “imperil” the Good Friday Agreement – brokered to establish peace in Northern Ireland after years of sectarian unrest. It comes after Mr Johnson unveiled plans to override key elements of last year's Brexit deal with the EU regarding Northern Ireland checks.