European Union's chief Brexit negotiator Michel Barnier takes part in the EU Commission's weekly college meeting in Brussels, Belgium, March 6, 2019. REUTERS/Yves Herman

STRASBOURG (Reuters) - The European Union’s Brexit negotiator Michel Barnier questioned whether there was any point in delaying Britain’s departure from the EU beyond March 29, saying on Wednesday that the British government would need to justify any request.

“Extend this negotiation -- what for?” Barnier asked in a speech to the European Parliament in Strasbourg. “It’s over.”

He said that whatever happened, the withdrawal treaty he had agreed with British Prime Minister Theresa May would remain the only deal on offer. He ruled out offering any more assurances on the controversial Irish backstop beyond those given by the EU to May on Monday, before the British parliament rejected the deal.

“If the UK still wants to leave the EU in an orderly manner, this treaty is -- and will remain -- the only treaty possible,” he said.