German manufacturers last night demanded that Britain be allowed to continue trading with the EU without any barriers.

The car-making industry said punishing Britain makes no sense – and it called on the German chancellor to give the UK a favourable trade deal.

Eurosceptics have repeatedly argued it is not in the EU’s interests to bring in tariffs as the UK imports more from Europe than it exports, and any weakening of the British economy would also have a ripple effect on Europe.

Matthias Wissmann, of the German Association of the Automotive Industry (VDA), said: ‘Even if many “experts” are competing to paint the worst possible scenario, now is the time for calmness.

Germany sells more cars to Britain than to any other country, with 810,000 exported last year (BMW plant pictured)

‘Every possible measure must be undertaken to enable the continued free movement of goods and services between the UK and the other EU countries. Following British departure from the EU, it will be in nobody’s interest to make the international flow of goods more expensive by erecting customs barriers between Britain and the European continent.’

Germany sells more cars to Britain than to any other country, with 810,000 exported last year, Mr Wissman said. And half of the 2.6million cars made in Britain last year were built by German-owned firms such as BMW, which runs Mini and Rolls-Royce.

Mr Wissman said: ‘We should do everything we can to ensure that this success story will be continued. Now it is up to Brussels to take action.’

Energy firm E.ON, which is based in Dusseldorf, is also lobbying against new customs barriers. Chief executive Johannes Teyssen said that ‘as far as possible’ EU leaders should aim to retain a ‘single market for goods and services for the British’.

Office for National Statistics figures show the gap between Britain’s EU exports and imports widened to £23.9billion in the first three months of this year– a record high. In 2000, 60 per cent of UK exports went to EU nations, but last year it was just 47 per cent.

German chancellor Angela Merkel has said there is ‘no reason to be nasty’ in Britain’s exit negotiations. Yesterday European leaders accepted it may take months for Britain to begin the process of leaving the EU as it is facing a ‘very significant political crisis’.

E.ON's chief executive Johannes Teyssen said that ‘as far as possible’ EU leaders should aim to retain a ‘single market for goods and services for the British’

German chancellor Angela Merkel has said there is ‘no reason to be nasty’ in Britain’s exit negotiations

Under the Lisbon Treaty, EU countries can leave through a process called Article 50, though it has never been used before. Triggering it starts a two-year clock for negotiating a formal exit.

European Parliament members had been pushing for David Cameron to trigger the exit process when he attends a Brussels summit tomorrow.

But last night diplomats from all 27 other member states agreed that it was unrealistic to formally begin exit negotiations until a new Prime Minister has been appointed.

The EU said yesterday that no negotiations could begin until the process was started formally, and officials warned that the UK would not be able to finalise a trade deal until after its exit.