Boris Johnson, Hammond in UK PM May's new Cabinet

Theresa May started her first full day in office as United Kingdom’s new prime minister on Thursday with a series of sackings after surprising many by naming “Leave” campaigner Boris Johnson as foreign minister against the backdrop of putting Britain’s exit from the European Union in motion.

May, 59, is unlikely to have had much sleep on her first night in Downing Street as after she had unveiled some of the main Cabinet posts it was time to take calls from European leaders, including German Chancellor Angela Merkel, French President Francois Hollande and Irish Taoiseach Enda Kenny.

“On all the phone calls, the Prime Minister emphasised her commitment to delivering the will of the British people to leave the EU. The prime minister explained that we would need some time to prepare for these negotiations and spoke of her hope that these could be conducted in a constructive and positive spirit,” a Downing Street spokesperson said.

Justice Secretary Michael Gove, who had challenged May in the Conservative Party leadership race, was among the first sackings announced on Thursday. He was replaced by Liz Truss, a former environment minister and one of the many female faces expected to occupy May’s team.

Education Secretary Nicky Morgan, Culture Secretary John Whittingdale and Cabinet Office Minister Oliver Letwin were other aides of former prime minister David Cameron dropped from the frontline and pushed to the party’s backbenches.

Health Secretary Jeremy Hunt, at the centre of the ongoing crisis and strikes by junior doctors over new controversial contracts, is expected to be shunted out to a different role.

In a clear indication that she intends to carve out a new path in government, May announced her first big shake-up just minutes after entering Downing Street on Wednesday evening by replacing George Osborne as UK Chancellor with Philip Hammond.

Former energy and climate change secretary Amber Rudd has been promoted in May’s new Cabinet as Home Secretary, the portfolio previously held by May herself, with Eurosceptic David Davis being made in charge of a new department for Exiting the European Union and being dubbed “Brexit minister”.

While Michael Fallon marked the only status quo Cabinet move by retaining the defence secretary’s job, the biggest surprise came in former London mayor Boris Johnson, who was appointed the new foreign secretary.

The star Brexit campaigner said he was “humbled” having been named the new foreign minister and is expected to work closely with India in his role that covers the Commonwealth countries, alongside newly-appointed international trade minister Liam Fox.

“We are living through an important moment in our country’s history. Following the referendum, we face a time of great national change. And I know because we’re Great Britain, that we will rise to the challenge,” May said in her first statement as PM. 

Acknowledging the biggest challenge awaiting in her in-tray, she added: “As we leave the European Union, we will forge a bold new positive role for ourselves in the world, and we will make Britain a country that works not for a privileged few, but for every one of us.”

European president Jean-Claude Juncker was among the first to write to the new PM to congratulate her and press her to start Brexit negotiations urgently.

The outcome of the vote to leave the EU “has created a new situation which the United Kingdom and the European Union will have to address soon,” Juncker said in his letter. 

“Leadership issue settled, now I expect we work quickly to deliver certainty,” he stressed.

Charles Michel, the Belgian prime minister, added his voice to those pleading for a speedy start to the Brexit procedure, following three weeks of financial and political turmoil triggered by the referendum on June 23. 

“We can’t afford a long period of uncertainty,” he said.

Davis, the newly-appointed minister in charge of the UK’s exit from the EU, has indicated that Article 50 of the Lisbon Treaty -- which triggers the formal two-year timeline for the exit negotiations -- will be triggered by the end of this year.