REUTERS/Yves Herman
European Commissioner for Economic and Financial Affairs Pierre Moscovici presents the EU executive's winter economic forecasts during a news conference at the EU Commission headquarters in Brussels, Belgium February 4, 2016.
Britons will vote June 23 on whether to remain a member of the EU. Asked in an interview on France 5 television whether the EU was planning what to do if they vote to leave, Moscovici said, "No, no and no, there is no plan 'B'. It doesn't help us in any way to envisage disaster scenarios."
"The day we start talking about a plan 'B' is the day we no longer believe in our plan 'A'. I have just one plan. The United Kingdom in a united Europe," Moscovici said.
The head of the European Commission, Jean-Claude Juncker, already made similar remarks last week as David Cameron was convincing European leaders to endorse his EU deal.
"If I would say now that we have a plan B, this would indicate a kind of willingness of the Commission to envisage seriously that Britain could leave the European Union.
"We don't have a plan B, we have a plan A. Britain will stay in the European Union as a constructive and active member of the Union," Juncker said.
Moscovici also said the EU's executive will not take part in the referendum campaign, saying any involvement could backfire.
"For me, it is prudent not to go campaign and try to impose a choice on a sovereign people. Referendums are dangerous, especially for Europe," he said.
Asked about the campaign that has kicked off with London Mayor Boris Johnson joining the call for Britain to quit the EU, Moscovici said the move could hurt Johnson's image.
REUTERS/Yves Herman
He said Europe was facing existential challenges, such as the Greek debt crisis and the current refugee crisis, but that the solutions should be at the European level.
"It is a lot of crises, but these are European problems, but they are also international. The idea that you could find national solutions to these problems which are international is a lie," he said.
"If there was a vote for Great Britain to leave the EU, it will be an inversion of the historic dynamic of the past years which has seen more countries join the bloc." Moscovici said.