Boris Johnson is offering Britain a vision of life outside the EU that is "intellectually impossible", a leading European finance minister has said.

The foreign secretary reportedly told a Czech paper the UK was likely to leave the EU customs union post-Brexit - but still wanted to trade freely after.

However, Jeroen Dijsselbloem, the Dutch finance minister, said such an option "doesn't exist" and was "impossible".
Number 10 said a decision on membership of the customs union had not been made.

Mr Johnson reportedly told the Czech newspaper Hospodarske Noviny he did not believe the UK would remain in the EU customs union after Brexit.

He was quoted as saying he believed such a move could be done while "maintaining free trade" with EU states, suggesting the UK could remain within the single market.

The customs union allows members to move goods without the imposition of tariffs on each other.

However, members also have to apply the same tariffs to goods that are imported from outside the union - which is seen as a disadvantage by some Brexit supporters who want the UK to be able to negotiate its own deals.

Speaking to the BBC's Newsnight, Mr Dijsselbloem - who is also president of the eurozone's Eurogroup - said Mr Johnson was putting forward options that "are really not available".

"He's saying things that are intellectually impossible, politically unavailable, so I think he's not offering the British people a fair view of what is available and what can be achieved in these negotiations," he said.

EU leaders have continually warned that the UK cannot expect access to European markets after Brexit unless it accepts the free movement of labour.

Mr Dijsselbloem said that while firms in the UK currently have full access to European markets "without any hindrance or customs duties", some of that "will disappear".

He said it would be "a step back", adding: "The UK will be outside the internal market and there will be some hindrances."
The Dutch minister told the programme that both the UK economy and the European economy would be in "a worse situation" post-Brexit.

"There is no win-win situation. It's going to be a lose-lose situation and in the best case if we set aside all emotions and try to reach an agreement that is least damaging to both of us we can minimise the damages," he added.

"We can do our best to minimise damages but it's going to be a step back and that is what Boris Johnson should start talking about."
Downing Street has insisted that the government's position has not changed and no decision has been taken on the future membership of the customs union.

It comes as Downing Street "wholeheartedly" rejected comments in a memorandum leaked to the press describing cabinet "divisions" over Brexit.

The document, compiled by consultancy firm Deloitte and obtained by the Times newspaper, says Whitehall is working on 500 Brexit-related projects and could need 30,000 extra staff.

It claimed there was no single government plan for how the UK will leave the EU.

The document also identifies cabinet splits between Mr Johnson, Brexit Secretary David Davis and International Trade Secretary Liam Fox on one side, and Chancellor Philip Hammond and Business Secretary Greg Clark on the other.

However, a Number 10 spokeswoman said the memo had been "unsolicited". Deloitte said there had been no "access" to Number 10 for the report.

Prime Minister Theresa May wants to invoke Article 50 of the Lisbon Treaty - beginning the formal two-year process for leaving the EU - by the end of March next year.