Brussels figures were reluctant to speculate in any specific terms about what the EU might demand in response to an extension request | Olivier Hoslet/EPA EU braces for Brexit extension request EU capitals want to prevent an extended divorce process from clouding the European Parliament election.

Prolonging Brexit? In principle yes, but give us a reason.

That's the demand from EU officials and national capitals on what U.K. Prime Minister Theresa May needs to explain if she requests an extension to Article 50 beyond the March 29 departure date.

But with political turmoil loosening May's grip on events in Westminster and another dramatic government defeat Wednesday evening, EU officials were reluctant to speculate in any specific terms about what the EU might demand in response to an extension request.

Following the vote in the House of Commons to rule out no deal on March 29, the prime minister will bring further votes Thursday on potentially extending Article 50. Her plan is to offer MPs either a short technical extension if they approve her Brexit deal in the coming days — in order to give time to pass necessary legislation, though it is highly unclear what might lead to a different outcome in a new ratification vote — or MPs would be presented with the prospect of a longer extension, which could mean the U.K. having to participate in the European Parliament election in May.

That would be deeply unpalatable to Brexiteers and politically toxic for the governing Conservative Party. In any event, the EU27 will be under no obligation to grant the U.K.'s particular request and could well counter with their own terms.

“There are only two ways to leave the EU: with or without a deal. The EU is prepared for both" — European Commission spokesperson

May’s implicit demand — that scores of British MPs make a complete about-face and reverse their vote from Tuesday with no new concession from the EU — suggested that political gravity was strongly pulling toward a long-term extension, provided that the EU27 agree.

May, in her statement, said she opposes a long extension. “I do not think that would be the right outcome,” she said.

In a statement after the vote, a European Commission spokesperson said the British parliament has failed once again to choose a path forward on Brexit and that rejecting a no-deal scenario is insufficient.

“We take note of the vote in the House of Commons this evening,” the spokesperson said. “There are only two ways to leave the EU: with or without a deal. The EU is prepared for both. To take no-deal off the table, it is not enough to vote against no deal — you have to agree to a deal.”

The spokesperson added: “We have agreed a deal with the prime minister and the EU is ready to sign it.”

EU27 ambassadors met on Wednesday morning ahead of the evening no-deal vote to consider the possibilities. The only thing they could agree for certain, according to officials briefed on the session, was that the decision on an extension and its terms must be taken directly by the 27 heads of state and government. Those leaders will meet at a summit in Brussels next week, where they are expected to hold their first formal discussion of what an extension might look like.

"The decision is so political," one senior EU official said. Diplomats and officials in Brussels are expected to prepare a list of potential options and the various implications and consequences for the heads of state and government to consider, but without expressing any recommendation or preference.

In Strasbourg, where the European Parliament was holding a plenary session, the EU's chief Brexit negotiator, Michel Barnier, expressed deep unhappiness over the uncertainty but also laid out some of the clearest parameters on an extension request.

"If the United Kingdom still wants to leave the European Union and leave it in an orderly fashion, then this treaty that we negotiated with Theresa May's government over the past year and a half remains the only treaty available," Barnier said.

Noting the upcoming votes in the U.K. parliament on preventing a no-deal scenario and on an extension, he said: "It will be for the British government to tell us — I hope positively — how it wishes to proceed, to finally bring together a constructive majority for a proposal. It is the U.K.'s responsibility to tell us what it wants for our future relationship, what its choice is, what its clear line is. We must now ask that question before asking about any possible extension."

"It's not clear to me how what hasn't been solved in two years could be sorted out in a few weeks" — German Europe Minister Michael Roth

And he emphasized that any extension must come with a purpose. "Extending the negotiation: For what reason? The Article 50 negotiation is now over. We have the treaty. It is here," he said.

At the Commission's regular midday news conference, chief spokesperson Margaritis Schinas repeatedly declined to speculate.

"I think there again we have been very clear in the past, we haven't received any request for an extension," he said. "Should there be a U.K. reasoned request for an extension, the EU27 will stand ready to consider it and decide by unanimity."

Asked what constituted a "reasoned request" he said, "I will not venture into a typology on what a reasoned request would be. I would simply state the obvious that a reasoned request is a request based on a reason."

Across Europe, other officials could only guess at where things might be headed.

"It's not clear to me how what hasn't been solved in two years could be sorted out in a few weeks," German Europe Minister Michael Roth said in a radio interview. "There would have to be a constructive and forward-looking suggestion — perhaps also one that's capable of getting a majority — on the table from the British side, which explains how they see all of this. And I don't see that at the moment."

Roth and several other officials said that the EU would almost certainly grant some kind of extension if requested, simply to avoid blame for a no-deal outcome.

"If there is a longer delay, more than a few weeks or beyond July 1, then Britain would have to take part in the European elections — and I have my doubts about whether that could be implemented," he added.

French President Emmanuel Macron, too, stressed that an extension had to come with a reason.

"If there's an additional delay, [the British] will have to explain to us what it is for, and that it won't be to renegotiate a deal we negotiated over the course of months," Macron said at a news conference in Nairobi.

An Elysée official said an extension would have to involve "a vision, concrete plans; we won’t have an extension to find ourselves in the same mess in a few months." The official added, "Right now, the 29th of March is the deadline, and we are preparing for a no-deal Brexit."

"The Brexit negotiations are like poker. There is no significant movement until the last second" — Austria's Finance Minister Hartwig Löger

The French official said that an extension request from the U.K. had to be reasonable but also noted the problem of the European Parliament election and said France would prefer that Britain's situation be resolved before the new Parliament is installed.

"Until June, OK, but beyond we will have a representation problem with the election, which will involve other issues," the official said. "So we have a preference for the extension to end by the beginning of the summer. Brexit can’t halt the European electoral process."

Austria's Finance Minister Hartwig Löger suggested there could still be a resolution that does not require an extension: "The Brexit negotiations are like poker. There is no significant movement until the last second. But in my personal opinion, there will be a solution at the very last moment."

Lili Bayer and Philip Kaleta contributed reporting.

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