It’s the Brexit catch-22, and it’s driving Britain’s political class crazy.

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The race to replace May has—so far—been mired in this seemingly intractable riddle to which no candidate has shown a convincing solution. Neither of the final two contenders seems to have any clear idea of how to solve it. Johnson has simply said the U.K. “must” leave by October 31, deal or no deal; Hunt, a multimillionaire businessman, claims he has the entrepreneurial skills to change the withdrawal treaty, a deal the EU has said, repeatedly, cannot be changed.

The only candidates in the race offering different solutions, however unlikely, were knocked out in earlier rounds of the Conservative-leadership race. The hard-liner Dominic Raab suggested suspending Parliament to bypass opposition to no deal, but this was seen as too extreme (and antidemocratic) for most Tory MPs; and the dovish Rory Stewart said the only solution was to stick with May’s deal and simply try to push it through Parliament again, even though it had failed three times already.

To those inside 10 Downing Street who have tried, and failed, to escape the trap for the past two years, the unfolding scene is like watching a TV history documentary on repeat, only this time run as farce. The reality, say some of those involved in the negotiations with the EU, is that unless the equation changes, whoever succeeds May as prime minister will be in the same tangled web that suffocated her premiership. The crisis, like catch-22, is one that cannot be escaped until the catch itself is changed—and, like Yossarian, that is not in the gift of the British prime minister. It is the system that is in control.

Only two bodies can undo this catch: the British Parliament, by changing its collective mind on the deal, allowing it to pass, or, alternatively, acquiescing to no deal; or the European Union, by changing the terms of the divorce to make it easier for Parliament to agree to it, or by cutting the cord and ejecting Britain from the club unilaterally. Ultimately, if the British political class has not found a way out of the riddle, European leaders can simply refuse to extend the country’s membership in the EU and, at 11 p.m. U.K. time on October 31, Britain will no longer be a member of the EU, deal or no deal. Catch-22 resolved.

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In European capitals, notably Paris and Dublin, this is more and more seen as the likely way out of the crisis. Arriving in Brussels yesterday, the Irish Prime Minister Leo Varadkar said while he had “endless patience” to keep extending negotiations with Britain to avoid it leaving without a deal, he was fast becoming a minority voice. Extensions, he continued, would likely only be granted if circumstances changed, and if time was needed for a general election or another Brexit referendum to break the impasse. “Some of my colleagues have lost patience, quite frankly, with the U.K., and there is enormous hostility to any further extension,” Varadkar said.