BRUSSELS — European Union leaders on Thursday agreed to extend the deadline for Britain’s looming exit from the bloc, but on terms different from those requested by Prime Minister Theresa May.
Thursday’s agreement is designed to avert the possibility of a disorderly, possibly chaotic, departure by Britain on March 29.
After hours of talks, the leaders decided that Britain’s exit date will be pushed back to May 22 if next week Mrs. May can persuade lawmakers in Parliament to accept her plan for leaving the bloc, which they have already rejected overwhelmingly, twice.
If she cannot persuade lawmakers to accept her plan, Mrs. May will get a shorter delay in exiting the European Union — until April 12. But Britain could stay in the bloc much longer if it decides it needs more time for a bigger rethink of Brexit, as the process is known.
If then, it would have to take part in elections to the European Parliament in May.
Speaking at a news conference after the extended deadlines were announced, Donald Tusk, president of the European Council, said that until April 12, “all options will remain open and the cliff edge date will be delayed.”
But he added that if there was no agreement in Parliament, and Britain had not indicated by April 12 that it was willing to take part in the European elections, “the option of a long extension will automatically become impossible.”
Thursday’s decision on extending the deadline was made by the leaders of 27 nations of the European Union, without Mrs. May. But she agreed to the decision.
Earlier, she had made a formal request for an extension until June 30, but did not tell her continental counterparts how she intended to proceed if she failed to get her deal through Parliament next week.
Asked at the news conference about the atmosphere during discussions with Mrs. May, Mr. Tusk diplomatically replied that it was “better than I expected.”
Frustration with Britain’s political dysfunction is palpable in Brussels, which has seen its agenda hijacked by the constant twists and turns of a government that is incapable of deciding what it wants.
And while Mrs. May insists she can muster the votes to ram her deal through in a third vote, her continental colleagues have largely lost faith in her ability to deliver on Brexit.
Her plan would eventually give Britain power over immigration from Europe, but tie the country to the European Union’s customs and trade system until at least the end of 2020.
Arriving at the European Union meeting in Brussels, Mrs. May refused to exclude the possibility of leaving the bloc without a deal if she cannot get her plan through Parliament next week.
“What matters is that we recognize that Brexit is the decision of the British people,” she said. “We need to deliver on that.”
But the sense of growing alarm is real.
”Our country is facing a national emergency,” the main British business and trade union groupings, the Confederation of British Industry and the Trades Union Congress, said in a rare joint statement.
“Decisions of recent days have caused the risk of no deal to soar,” the statement said. “Firms and communities across the U.K. are not ready for this outcome. The shock to our economy would be felt by generations to come.”
Under the British government’s “Operation Yellow Hammer,” more than 5,000 personnel will begin on Monday to prepare for the chaos expected if Britain crashes out of the bloc with no agreement. Critics have already dismissed that as too little, too late.
In Brussels on Thursday, European officials also were host to talks with Jeremy Corbyn, the leader of the opposition Labour Party, which wants closer ties to the European Union than do Mrs. May’s Conservatives and could play a critical role in the way things unfold in London.
If Mrs. May, against the odds, does succeed in Parliament next week, then matters move relatively smoothly, with a modest delay to Brexit to allow for enacting legislation to put her plan in place.
But the prime minister’s angry denunciation of lawmakers in a national address Wednesday evening is unlikely to make it any easier to win over opposition legislators.
The Europeans do not want to be seen as responsible for the disaster of a no-deal exit. Not only would this hurt their economies, but it could leave a bitter legacy with a big and important neighbor while complicating the bloc’s finances.
Mrs. May, though, has been hinting that she might prefer a no-deal Brexit, even if that outcome was opposed overwhelmingly in Parliament.
She has always jealously guarded the interests of the Conservative Party, and she would reasonably fear that calling for a lengthy extension could split the party irrevocably.
Britain has the power to withdraw its decision to leave the bloc — as opposed to requesting an extension of negotiations — and could do that unilaterally. Yet it is almost impossible to imagine Mrs. May doing this, since she has vowed to deliver Brexit one way or another.
That has prompted speculation that, if Mrs. May loses again next week, she could face a leadership crisis, particularly if she tries to pursue a no-deal Brexit. But it would be hard to force her out, even if more pro-European cabinet ministers threatened to quit.
And resigning would be out of character for a leader who by nature and character has been willing to endure scorn, humiliation and divisions as she pursues what she considers to be Britain’s best version of Brexit.
Dalia Grybauskaite, the outspoken president of Lithuania, favors patience with Britain. “We will be supportive to the prime minister, in any way we can,” she said.
“We need to be prepared for everything, but of course we will do everything to find a solution,” Ms. Grybauskaite said.
Another European Union meeting was “possible,” she said, adding that the bloc would try to do everything it can to avoid no deal.
“But I’m not sure we can,” she said, “because a lot of things depend on the U.K. side, not on Brussels.”