Boris Johnson has stepped down as foreign secretary — becoming the third minister to resign in 24 hours, rather than back Prime Minister Theresa May’s plans for a soft Brexit. 

Health secretary Jeremy Hunt replaces Johnson in the role, with culture secretary Matt Hancock taking over Hunt's previous office.

The resignation was announced on Monday afternoon, with Downing Street putting out a statement saying, “This afternoon, the prime minister accepted the resignation of Boris Johnson as foreign secretary... The prime minister thanks Boris for his work.”

Johnson's letter of resignation lamented that the Brexit "dream is dying, suffocated by needless self-doubt" — and accused May of pursuing a "semi-Brexit." May responded by saying she was "sorry — and a little surprised," pointing out that Johnson had supported her plans following the all-day Chequers summit on Friday. 

However, it had emerged that Johnson had referred to efforts to support May’s Brexit plan as being like “polishing a turd." 

Johnson was one of the leading voices of the 2016 Brexit campaign.

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Johnson’s resignation follows David Davis stepping down from his post as Brexit secretary on Sunday, and Steve Baker resigning his role at the Department for Exiting the EU. 

For Johnson, it means that he’s no longer in the cabinet and he goes back to being a backbench MP. 

"This is a time when the world is looking at us as a country, wondering what type of country we are going to be in a post-Brexit world," said new foreign secretary Jeremy Hunt. "What I want to say to them is Britain is going to be a dependable ally, a country that stands up for the values that matter to the people of this country, and will be a strong confident voice in the world."

But what does it mean for Britain?

Johnson’s resignation is likely to heighten the chance that May could face a vote of “no confidence,” according to reports. 

A “no confidence” vote would come about if 15% of Tory MPs — so, 48 MPs in total — write a letter to the chair of the backbench 1922 Committee, Graham Brady. MPs can write their letter anonymously if they choose, or they can even tweet or WhatsApp Brady.  

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If more than 48 MPs write a letter, then it would result in a vote of no confidence, which could lead to a leadership challenge. 

In a leadership challenge, the prime minister would automatically be a candidate if she wanted to be, and other people from outside the cabinet can put themselves forward. 

Johnson’s resignation from the cabinet has prompted speculation that he would be likely to put himself forward as a candidate in a leadership election. 

The winner of the leadership election is the person who gets more than 50% of Tory MPs’ vote. Commentators, however, believe at this stage that no one would be likely to get the number of votes needed to oust May. 

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There’s no public involvement in the leadership election, unless May is ousted. If she is, there would likely be a proper leadership election, where the two candidates with the highest level of support would face a vote from the Tory party membership. 

The winner of that vote would be the new Conservative leader. The timeframe of the vote would be set by the 1922 Committee, but it would likely come about quickly given that the UK has some pretty important decisions to make this year. 

If she’s not ousted, May could still struggle to rally enough support for her Brexit deal. If there wasn’t enough support, Britain could face crashing out of the EU without a deal. 

The resignation could also have potential ramifications for UK aid — which is a vital tool in the effort to support some of the world's most vulnerable people. The UK has currently pledged to put 0.7% of its gross national income towards the UK aid budget, and that pledge is enshrined in law. 

But if there were to be a leadership election within the Conservative party, where there are a number of outspoken voices against UK aid, that could put pressure on the UK's current pledge and reignite questions about the value of UK aid. 

In her first public appearance following the resignations, May paid tribute to Davis and Johnson for “their work over the last two years.” 

She said Johnson brought “passion” in promoting a “global Britain” to the world, according to the Financial Times.