Britain's Brexit plans rocked by resignation

Britain's Brexit plans were in turmoil today after the UK's ambassador to the EU quit, blasting "ill-founded arguments and muddled thinking" less than three months before the process is due to start.

Ivan Rogers' resignation and sharp criticism shed new light on the difficulties faced by Prime Minister Theresa May, who wants to hand in Britain's notice for withdrawing from the European Union by the end of March.

The move to trigger the Article 50 mechanism would start a two-year clock ticking on sorting out future relations between Britain and the EU before it leaves the bloc.

Rogers said yesterday he accepted his departure would add to the "uncertainty" over the coming years of Brexit negotiations.

May has faced criticism for saying little about Britain's divorce settlement objectives: last month she went beyond her "Brexit means Brexit" mantra to specify that she wanted a "red, white and blue Brexit".

And Rogers made clear that he knew little more about how Britain intended to tackle thrashing out its future relationship with the EU.

A highly-regarded diplomat who had been due to end his four-year stint in October, Rogers quit nine months early so his successor could see through the whole Article 50 process.

However, he left with some pointed remarks in his resignation email to staff at UKRep, Britain's EU embassy.

"We do not yet know what the government will set as negotiating objectives for the UK's relationship with the EU after exit," he said, revealing that UKRep were no clearer on the issue than what May has made public.

Rogers urged colleagues to provide British ministers with their "unvarnished" understanding through Brexit negotiations -- "even where this is uncomfortable".

"I hope you will continue to challenge ill-founded arguments and muddled thinking and that you will never be afraid to speak the truth to those in power," Rogers said.

He also criticised the British government for its short supply of "serious multilateral negotiating experience" in London and said the structure of the UK's negotiating team "needs rapid resolution".

Rogers came under fire last month for saying it could take 10 years for Britain to conclude a trade deal with the EU.

The government insisted, though, that he was only reporting back what was being said in European capitals.

The mild-mannered Rogers is widely respected in Brussels where he is known as a vastly experienced operator.

His critics say he is a europhile, but European diplomatic sources described him as being a realist.

British diplomatic sources at the time of the leaked "10 years" comments voiced suspicions that he may have been knifed in the back by pro-Brexit forces who wanted him out.

The European Commission said today it regretted, just as London prepared to launch fraught Brexit divorce negotiations.