The resignation of U.K. Foreign Secretary Boris Johnson on Monday afternoon has led to suggestions that the British government is on the brink of collapse. Johnson stepped down after Prime Minister Theresa May outlined her government’s desire for a softer version of Brexit. He is the second cabinet minister to resign within 24 hours after the U.K.’s main Brexit negotiator, David Davis, quit late Sunday night. A statement released by Downing Street confirmed Johnson’s departure and said a replacement would shortly be announced. Later, in a statement to parliament, May thanked the “work” of Davis and “passion” of Johnson while noting their differences in opinion with her over Brexit. That gratitude may not last long with many seeing the resignation as a pre-cursor to a leadership challenge, which would bid to topple May and replace her with a more ardent supporter of Brexit.

Britain's Prime Minister Theresa May holds a press conference at the end of the second day of the G7 Summit on June 9, 2018 in La Malbaie, Canada. Neal | Getty Images

The prime minister would have to conduct a leadership contest if at least 48 of her own lawmakers were to move against her. The process for that involves politicians sending letters calling for a vote of confidence to the powerful 1922 committee of backbenchers. Once that threshold has been reached, the committee's chairman will announce the start of the contest and invite nominations. That committee, which May is due to address at 5:30 p.m. local time (12:30 p.m. ET), coordinates the views of May’s Conservative Party in the House of Commons. It is believed that anything less than a strong showing from May at this meeting will trigger a leadership contest. The former UKIP leader Nigel Farage, who is considered by some as the architect of Brexit, took to Twitter congratulating Johnson on his resignation and said it was time to get rid of the "appalling Theresa May." Tweet 2 Jeremy Corbyn, the leader of the opposition Labour Party, said it proved that Theresa May was incapable of negotiating a Brexit deal with the EU, given the splits within her own party. Tweet 1 In Brussels, the European Union (EU) President Jean-Claude Juncker offered a sarcastic assessment, noting that last week’s meeting to agree the U.K.’s Brexit position had failed. “This clearly proves that at Chequers there was a big unity of views in the British cabinet,” he said to reporters.

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