LONDON - London could not remain Europe’s financial centre if Britain left the European Union at an upcoming referendum, top European politicians said on Monday, warning that reaching a free trade agreement with Britain would not be the bloc’s priority.

A European Union flag and the United Kingdom's Union flag fly outside Europe House, the office of the European Commission in London, Britain January 20, 2016. REUTERS/Stefan Wermuth

Painting a bleak picture for Britain outside the EU during a simulated negotiation of what would happen in the event of an “out” vote, politicians from several European countries said Britain would not be able to “cherry pick” a new deal post-exit.

“There is no such thing as a free lunch. Brexit is something which does not only affect you but affects our country,” said former German deputy finance minister Steffen Kampeter.

“The cherry-picking proposal, after torturing us over months, is not acceptable.”

Kampeter said Germans would not back their government agreeing to a post-Brexit deal that gave London an advantage over Frankfurt as a financial centre, while former Irish Prime Minister John Bruton said Dublin would seek to take London’s crown.

Former Italian prime minister Enrico Letta said Italy would support moving Europe’s financial centre away from London if Britain left the bloc, while France’s Noelle Lenoir, a former minister of European Affairs, said the opportunity to move the EU’s financial hub to a euro zone country “could be a blessing”.

“How can you expect that after you leaving the European economy ... that economy would accept that its financial centre is outside its borders,” said Karel de Gucht, former European Commissioner for Trade, representing the EU institutions in the debate hosted by think tank Open Europe.

Representing Britain, former finance minister Norman Lamont said Britain would seek to cooperate with its former partners in areas such as trade and security, but the other eight countries represented quickly lined up to make clear it would not get an easy ride.

“You were our best friend, and we had a marriage. Now we are divorced,” said former Swedish Minister for Trade Ewa Bjorling.

Bruton said Ireland expected the European Commission “to drive a very tough deal” with Britain in any trade talks, while others said the EU’s priority would be completing existing negotiations such as the TTIP deal with United States.

Others were wary of making exit attractive to increasingly popular anti-EU groups in countries such as France and Spain.

“The common interest of the remaining members is to deter other exits,” said Leszek Balcerowicz, former Deputy Prime Minister of Poland. “This should have an impact on the terms Britain gets - they should not be too generous.”