A senior member of Chancellor Angela Merkel's Social Democrat coalition partner, Axel Schafer said the PM's hope that President-elect Trump will look favourably on the UK will come to nothing.
Referring to the shock election of Mr Trump, Mr Schafer told The Times: “What changed is the likelihood of a speedy and preferential trade deal between UK and US.
“Even before Tuesday the chances were rather low, now the hope for this kind of deal seems delusional.”
The pointed remarks came after ministers talked-up the chances of a close working relationship with the surprise winner of the race to the White House.
Underlining the starkly different approach to Mr Trump taken by London and the continent, Foreign Secretary Boris Johnson told his EU counterparts to end the “whinge-o-rama” over the outcome of the US election.
The comments came as Liberal Democrat leader Tim Farron said his party would vote against triggering Article 50 which formally launches withdrawal negotiations with the EU, unless there was a guarantee that the final Brexit deal with Brussels is put to a fresh referendum.
He insisted he respected the decision made by voters in favour of leaving the EU but said nobody should have a deal “imposed” upon them.
Although the Lib Dems only have eight MPs they have more than 100 peers in the Lords, which could spell trouble for the Government if judges rule that a full Act of Parliament is required before Article 50 can be triggered, as the legislation would have to clear both Houses.
Mr Farron said he believed the Lords would not get a vote either for or against Article 50 but would be able to move amendments.
The Lib Dem leader said: “We have said we will vote against Article 50 if our red line is not met, and it is a single, simple red line which is that we want to respect the will of the people and that means that they must have their say in a referendum on the terms of the deal.
“It is the only logical and it is the only democratic option on the table. There will be a referendum at the end of this process so that nobody would have imposed upon them something they didn't vote for.”
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