By Ian Dunt Follow @IanDunt
Britain will not be able "get away" from efforts to stabilise the eurozone, the parliamentary leader of Germany's ruling party has announced.
In comments which will enrage eurosceptics, Volker Kauder told the Christian Democratic Union conference that Britain will have to accept a tax on financial transactions without waiting to see if the US will follow suit.
"Britain had a responsibility to make Europe a success," he said.
"I can understand that the British don't want that [a transactions tax] when they generate almost 30% of their gross domestic product from financial-market business in the City of London.
"Only going after their own benefit and refusing to contribute is not the message we're letting the British get away with."
The prime minister's spokesman said: "There is clearly going to be a debate about Europe and the shape of Europe over the coming weeks, months and years. What we would say is that the crisis means that we should focus on the economics."
European leaders are increasingly frustrated with Britain's refusal to become involved in eurozone rescue plans, despite relying on a recovery at least as much as its members.
French president Nicolas Sarkozy allowed his irritation with David Cameron to become public last month, when he told the prime minister: "We’re sick of you criticising us and telling us what to do.
"You say you hate the euro, you didn’t want to join and now you want to interfere in our meetings."
Europe's response to the eurocrisis presents a variety of problems for Downing Street.
Mr Kauder's suggestion that Europe would submit to tighter fiscal discipline would likely see greater political cooperation, opening up the possibility of treaty changes significant enough to trigger a referendum in Britain.
Such an eventuality would pull coalition tensions to breaking point, as both governing parties pull in different directions.
"Now all of a sudden, Europe is speaking German," Mr Kauder said.
"Not as a language, but in its acceptance of the instruments for which Angela Merkel has fought so hard, and with success in the end."