Political battle over Britain’s exit from EU now moves to Parliament.

British Prime Minister Theresa May secured cabinet approval for her Brexit deal Wednesday evening, clearing an important hurdle but setting the stage for a battle in Parliament that could shake her government and unravel the agreement with the European Union for Britain’s orderly withdrawal. Following a five-hour meeting, Mrs. May’s ministers gave the green light to a plan that would keep the U.K. bound to the EU for many years after the country formally leaves the bloc in March. The prime minister appeared to avoid an immediate revolt by her own ministers, some of whom have openly criticized her Brexit plan. “This is a decision which will come under intense scrutiny,” she said, standing outside No. 10 Downing Street. “This is a decision which is in the best interest of our entire United Kingdom.” The cabinet decision clears the path for the deal to be officially presented to EU leaders at a summit expected this month. However, far tougher battles lie ahead for Mrs. May, as time runs perilously close to the March 29 date of the U.K.’s exit from the bloc. She still must secure approval of the deal in the British Parliament, where she faces open hostility over the plan from both the opposition Labour Party and members of her own Conservative Party.

The compromise deal allows the U.K. to maintain close ties to the EU, its biggest trading partner, while also reclaiming control over its borders. But that leaves the deal open to criticism from U.K. lawmakers on both sides of the debate who say it is the worst of both worlds, neither breaking with the EU nor fully staying in. A key concern: how it will ensure that no hard border emerges on the island of Ireland after Brexit is implemented.

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