FILE PHOTO - A British Union Jack flag is seen on the desk of a Member of the European Parliament ahead of a debate on Brexit after the vote on British Prime Minister Theresa May's Brexit deal, at the European Parliament in Strasbourg, France, March 13, 2019. REUTERS/Vincent Kessler

ZURICH (Reuters) - Britain must take part in European parliamentary elections if its departure from the European Union is pushed back beyond July 1, Austria’s delegate to Brexit negotiations said in an interview published on Saturday.

British Prime Minister Theresa May is expected to head to Brussels next week to request a short delay to the exit process after the UK parliament on Thursday voted in favour of extending negotiations beyond the original March 29 deadline.

“We have to wait and see what the government in London actually proposes. If there is an extension beyond July 1, then in any event, the United Kingdom must vote in May for the European elections,” Austrian diplomat Gregor Schusterschitz said in an interview with Austrian newspaper Der Standard.

“The EU has never been the side in the negotiations that has rejected something for reasons of principle. This also applies to the question of the extension: it shouldn’t fail because of us.”

Several EU leaders have already said Britain must either have left before a new European Parliament is elected in May to take office in July or must hold its own EU election in order to avoid any legal challenge to the legitimacy of the legislature.

In the interview, Schusterschitz also said the EU might have been too soft on Britain and allowed it too long to conduct a largely domestic discussion, which involved less debate with the EU than it did internal political back-and-forth.

“Maybe we could have been more brutal sometimes,” he said. “We didn’t do that, and so we probably allowed British politics too long to fool around - and not face the really difficult questions, which are being discussed now, much earlier.”