"The Queen has been pleased to approve the appointment of.Sajid Javid MP as secretary of state for the home department", a Downing Street statement said.
Those tipped to replace her include Communities Secretary Sajid Javid; reformist Environment Secretary Michael Gove, a pro-Brexit figurehead; and Health Secretary Jeremy Hunt, who reportedly refused to budge during the last reshuffle.
Britain's Prime Minister Theresa May faced the headache of another cabinet reshuffle on Monday after interior minister Amber Rudd quit having "inadvertently misled" lawmakers about deportation targets for illegal immigrants.
He was instructing the press office to brief people like me that "there are no removal targets for immigration enforcement officers, regional or national".
Mr Javid said the phrase "hostile" was "unhelpful and does not represent our values as a country", preferring "a compliant environment".
In response, May said she believed Rudd had given her evidence to the House of Commons "in good faith" but that she understood her decision to resign and take "responsibility for inadvertently misleading the home affairs select committee".
Now here is the mystery.
The dramatic exit of close ally Rudd came as a setback for May, whose centre-right Conservative Party faces potentially bruising local authority elections across metropolitan England on Thursday.
His father moved to Britain from Pakistan and worked as a bus driver in Bristol.
In a series of late night tweets, Ms Rudd said she had not seen the memo - even though it was copied to her office - but admitted that she should have been aware of the targets.
"This is important. If you talk to members of the public they want to ensure that we are dealing with people who are here illegally".
Despite government apologies and assurances to the contrary over the ongoing Windrush scandal, several United Kingdom residents were believed to have been subject to threats of deportation back to Jamaica, a Commonwealth nation, over their legal status.
He backed the losing Remain campaign in Britain's 2016 referendum on its European Union membership, but his pro-EU position was lukewarm.
Britain's government launched a review on Wednesday into the treatment of some Caribbean migrants who were invited to Britain after World War Two but have been left without documents and denied basic rights.
Immigration control remains a hot topic in the United Kingdom and was a factor in the Brexit vote.
However, many never formalised their status, often because they were children who came over on their parents' passports and then never applied for their own.
The government has apologised to Windrush migrants and their families, promised citizenship and compensation to those affected, including to people who have lost their jobs and been threatened with deportation because of the errors.
A 2017 letter to the PM in which Ms Rudd spoke of her plans to increase removals "by more than 10 per cent over the next few years" did not relate to a target but to an "aim over a non-specific period", the Prime Minister's spokesman said.