EU leaders reject claims that Britain will escape a multi billion-pound ‘divorce bill’ it if walks away with no post-Brexit deal, the UK’s ‘man in Brussels’ has warned.

Sir Tim Barrow, Britain’s ambassador to the EU, sought to dampen growing Brexiteer enthusiasm to quit without paying “a brass farthing” as one Conservative MP put it.

“My counterparts have an interest in other legal opinions which have been forthcoming, which offer a different interpretation,” Sir Tim told a parliamentary inquiry.

The view appeared to open up a split with David Jones, a minister in the Brexit department, who welcomed the ‘no exit fee’ argument – first put forward in an explosive House of Lords report.

Mr Jones said: “Certainly the House of Lords committee report was extremely helpful. I’m sure it’s not gone unnoticed in Brussels and in other European capitals.”

The split came as Sir Tim gave an update verdict on the prospects for Britain agreeing a framework for future trade with the EU within the two years of the Article 50 negotiations, to start next month.

His predecessor, Sir Ivan Rogers – who quit abruptly in January, condemning the Government’s “muddled thinking” – warned it would take until the mid-2020s to achieve a free trade deal.

But Sir Tim said such “speculation” was based on the difficulty of striking deals between countries with very different trade systems, when Britain and the EU already had “convergence”.

“On the first day after withdrawal there will be convergence – we are creating something different,” he told the Commons European Scrutiny Committee.

“Our mandate is clear to get on with it. There’s a timetable that everybody has bought into included in the treaty and that’s what we are going to do.”

The Article 50 process clearly stated that the EU should take account of its “future framework” with the UK, as well as agree the exit deal.

Mr Jones agreed that the UK was at a “huge advantage” in negotiating a trade deal because its current arrangements were “already in alignment” with the bloc’s standards.

EU negotiators are expected to present Theresa May with a bill as high as £50bn – for outstanding liabilities – and refuse to discuss a trade deal until Britain has agreed to pay up, at least in principle.

The UK currently pays about 12 per cent of the EU’s budget, which means its withdrawal will impose bigger financial burdens on the likes of Germany and France.

The committee’s chairman, Sir Bill Cash, summed up the mood among many Brexit-backing Tories when he said: “We really don’t owe anything to the European Union.”

The evidence session came within a couple of hours of Downing Street announcing that Article 50 will be triggered on March 29, in a letter sent to EU Council President Donald Tusk.

After he resigned, Sir Ivan warned that Whitehall departments were not engaging properly with the EU on day-to-day business because Brexit was a distraction.