The European Union's chief negotiator has said "I can't negotiate with myself", as he warned Britain may be running out of time to reach a Brexit deal.
Michel Barnier said Theresa May's government must begin talks "very quickly" as he noted that in three months since Article 50 was triggered "we haven't progressed" toward reaching a deal before the looming March 2019 deadline.
The Prime Minister has talked up her plans to get on with negotiations, due to begin within days.
She "has directed that the procedures for preparing the negotiations for the formal withdrawal from the European Union should start as soon as possible," the Government told the European Commission on Friday.
Mr Barnier told the Financial Times: "My preoccupation is that time is passing, it is passing quicker than anyone believes because the subjects we have to deal with are extraordinarily complex.
"It will take us several months to draw out the conditions of an orderly withdrawal. Let’s not waste time.
"I’ll say it clearly: there’s no spirit of revenge, no punishment, no naivety either. And there is truth. Truth on what Brexit means, what leaving the EU signifies by its consequences. The citizens have the right to know."
"Lots" of Britons underestimated what those consequences would be, he added.
It comes as a report claimed Labour and Conservative MPs had met for secret talks aimed at urging Ms May to take a cross-party approach to Brexit.
The Scottish Conservatives' leader Ruth Davidson, whose influence has increased dramatically with the election of 13 Tories north of the border, has broken ranks to say: "This isn't just going to be a Tory Brexit."
Ms May's position in the Commons was weakened as a result of losing her majority in the general election, fuelling speculation she will be forced to alter her approach to the Brexit negotiations.
In a bid to shore up her ability to wield power, she was negotiating with DUP leader Arlene Foster on a support deal on Tuesday.
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