Britain will be shut out of the Single Market if she opts to leave the European Union (EU), Germany’s finance minister Wolfgang Schäuble has threatened. But Leave campaigners have questioned whether German manufacturers would welcome the move, and accused the government of putting him up to it.

Speaking to Der Spiegel, Mr Schäuble insisted that Britain would not be able to follow the examples of Switzerland and Norway and be part of the single market while retaining political independence, saying: “It would require the country to abide by the rules of a club from which it currently wants to withdraw.

“If the majority in Britain opts for Brexit, that would be a decision against the single market. In is in. Out is out. One has to respect the sovereignty of the British people.”

But Leave campaigners have suggested that the minister’s comments were a hollow threat, as erecting trade barriers would not be in Germany’s interest.

“The Eurozone economies are dependent on trade with the UK,” a spokesman for the official leave campaign said. “We are the fifth largest economy in the world, while many of them are in a desperate state due to the failing single currency. It would be perverse of the Eurozone to try to create artificial barriers and would do far more damage to them than to anyone else.”

Yesterday, newly released figures from the Office of National Statistics showed that Britain’s goods trade deficit with the EU widened to a record high of £23.8 billion over the last three months. Leave campaigner Steve Baker MP said that the statistics “show the trade balance is overwhelming in favour of the UK securing a free trade deal with the EU.”

Mr Schäuble seemed nonchalant about the prospect of such an outcome, however.

“Europe will also work without Britain if necessary,” he predicted, adding: “At some point, the British will realise they have taken the wrong decision. And then we will accept them back one day, if that’s what they want.”

But he acknowledged that a British vote to leave the Union could be the trigger for similar referenda across the member states.

“You can’t rule it out,” he said. “How would the Netherlands react, for example, which has traditionally had very close ties to Great Britain?”

He argued that, for that reason, a Brexit – or even a slim vote to remain – must not be met with calls for further integration measures.

“It is important for the EU to send the message that it has understood the vote and it is prepared to learn from it, he said.

“In response to Brexit, we couldn’t simply call for more integration. That would be crude; many would rightfully wonder ­whether we politicians still haven’t understood. Even in the event that only a small majority of the British voters reject a withdrawal, we would have to see it as a wake-up call and a warning not to continue with business as usual. Either way, we have to take a serious look at reducing bureaucracy in Europe.”

Iain Duncan Smith, the former work and pensions secretary, said of Schäuble’s comments: “To quote Mandy Rice-Davis, he would say that, wouldn’t he?” The Guardian reported.

“What I call the realpolitik underneath the surface is that they don’t want to get into spats. Of course they don’t. We’re a friend, we cooperate in NATO, the G8 and G20. Mr Schäuble’s bound to say what he said. Come on. Don’t tell me that Mr Osborne hasn’t been on that line to him almost permanently for the last few weeks…

“You’ll probably get a load of these statements. Every finance minister in Europe is going to line up. They’ve probably got them every day between now and the referendum.”

The interview with Mr Schäuble was conducted by Der Spiegel as part of an edition pleading with British voters: “Don’t Go!”

Appealing for a Remain vote, the magazine said it was “unbelievable that they [the British] don’t seem to see how much they’ve shaped the continent, how much we value them here, how close we Germans feel to them”.

Follow Donna Rachel Edmunds on Twitter: or e-mail to: dedmunds@breitbart.com//