U.K. lawmakers in Prime Minister Theresa May’s Conservative party hit back at claims from Austrian Chancellor Christian Kern that Britain will be charged 60 billion euros ($63 billion) to leave the European Union as tensions surge ahead of Brexit talks.

In a Bloomberg interview on Thursday, Kern became the first EU leader to put a value on the size of the U.K.’s Brexit bill. While May’s office was muted in its public comments, Kern’s warning that there would be “no free lunch” for the U.K. sparked a furious response from senior members of Parliament.

“This figure is a nonsense that’s been conjured up by EU officials who are behaving like children,” former cabinet minister Iain Duncan Smith said in an interview. "For the Austrian chancellor to even refer to it is quite absurd. As for saying there’s going to be no free lunch for Britain, we paid so much into the EU budget over the years, we pretty much bought the damned restaurant."

Haggling over the Brexit bill looks like it will mark a testy start to the negotiations once May invokes Article 50 of the Lisbon Treaty, something she has said she’ll do before the end of March. Britain’s Trade Secretary Liam Fox has called the very idea of a charge “absurd” and the government in London is adamant it won’t pay for any EU projects signed after November.

David Fuller's view

This is a sign of weakness and will have no impact on UK Brexit considerations.  The EU has a budget problem and is not known for its spending cuts.  Therefore, this financial threat is a loud if indirect warning to French and Italian voters not to consider leaving the EU.