British Prime Minister Theresa May postponed the final vote on her Brexit deal Monday after the European Court of Justice ruled that Britain can unilaterally call off its exit from the European Union without input from the 27 other EU members, and without altering the terms of Britain's EU membership. On Tuesday, Britain's House of Commons was scheduled to vote on, and expected to reject, the Brexit plan, which would have thrown Britain's exit from the EU into further uncharted waters. The deal under consideration was settled with EU leaders late last month. Revoking the Article 50 exit clause would have to "follow a democratic process," the court ruled, meaning that in Britain, Parliament would have to approve calling off Brexit. The upshot is that staying in the EU is now "a real, viable option," BBC Brussels correspondent Adam Fleming notes, cautioning that "a lot would have to change in British politics" for Brexit to be actually called off.