Nancy Pelosi, America's third most powerful politician, warned today that a breakdown in the talks over the Northern Ireland Protocol would be 'problematic' for a post-Brexit UK-US trade deal. The Speaker of the US House of Representatives, who is currently visiting Britain, has been critical of Prime Minister Boris Johnson's approach to Northern Ireland following the UK's exit from the European Union. The pair discussed the issue in Downing Street yesterday and Mrs Pelosi today expanded on her views about the talks underway between the UK and Brussels to resolve issues ... ....Mrs Pelosi, 81, said she felt it would...