Exit the Brexit hero: after three years and 44 days, barely more than Theresa May, whom he replaced in 2019, Boris Johnson is leaving what he called "the best job in the world", after a series of scandals having triggered dozens of resignations in his close entourage in early July.
He was the 14th Prime Minister of the 96-year-old sovereign. Since his forced resignation in July, he had remained in charge of day-to-day business in Downing Street, the time to appoint his successor.
The transfer of power takes place at Balmoral, the summer residence of the monarch, and not at Buckingham Palace in London as is the tradition, because of the mobility problems of the queen.
Elected by 57% of some 142,000 voting members of the Conservative Party, against 43% for her rival, former finance minister Rishi Sunak, Ms. Truss, 47, until now foreign minister, must then return to London to s address the British in the afternoon.
She promised Monday to govern "like a conservative", and pledged to put in place "a bold plan to reduce taxes and grow our economy".
Under pressure to help millions of Britons facing skyrocketing energy bills, she also vowed to tackle "the energy crisis by (taking) care of people's energy bills, but also by (dealing with) long-term energy supply difficulties".
The third woman to enter Downing Street after Margaret Thatcher (1979-1990) and Theresa May (2016-2019), her government's announcement on Tuesday will be a first test for Ms Truss, who campaigned far to the right.
His finance minister should be Kwasi Kwarteng, 47, until now energy secretary, a supporter like Ms. Truss of a more modest state and a more deregulated economy.
Suella Braverman, 42, until now legal adviser to the government, and initially candidate for the post of Prime Minister, is approached for the Ministry of the Interior. Very on the right, she will inherit the file of the thousands of illegal migrants arriving on the British coasts, that the one who preceded her wanted to send to Rwanda.
James Cleverly, 53, Minister of Education after having been Secretary of State for European Affairs, should move to Foreign Affairs. Ben Wallace would remain at the Ministry of Defence.
Mr. Kwarteng is of Ghanaian origin, Ms. Braverman of Indian origin, and Mr. Cleverly's mother was from Sierra Leone, a diversity never before seen in these key positions.
First announcements to try to stem the economic crisis are expected by the end of the week. After opposing it for most of her campaign, Liz Truss could announce an energy price freeze, with still unclear outlines, to help households and businesses, according to British media.
- Unite the party -
Ms. Truss, who advocates controversial tax cuts to boost growth, and a tight government, will have a lot to do to rally behind her a divided Conservative party, in power for 12 years. Many deputies would have preferred Rishi Sunak to him, more nuanced and considered more able to manage the crisis.
Calls for unity have multiplied, led by outgoing Prime Minister Boris Johnson who has asked the Tories to "support it 100%".
"The enemy is Keir Starmer", the leader of the Labor opposition, underlined a deputy, especially as the polls give the Labor largely winners in the next legislative elections, scheduled for January 2025 at the latest.
When announcing her victory, Ms Truss paid tribute to her 'friend'. "Boris, you got Brexit done, you crushed Jeremy Corbyn (former Labor leader, editor's note) you rolled out the (anti-Covid) vaccine and you stood up to Vladimir Putin" after the invasion of Ukraine, a she listed.
After leaving Downing Street, Boris Johnson remains an MP. To date he has not said anything about his future intentions.