The UK’s new Prime Minister Rishi Sunak has issued a plea for unity in the face of a "profound economic challenge".
He won the Tory leadership contest yesterday after rival Penny Mordaunt failed to secure enough backing from MPs.
Mr Sunak said bringing his party and the country together would be his "utmost priority".
He will become the UK's first British Asian prime minister and the youngest PM for more than 200 years.
Mr Sunak - a 42-year-old practising Hindu - is expected to take office today after being formally appointed by the King.
He replaces Liz Truss, following her resignation just 45 days into her tumultuous premiership last week.
No.10 statement
The BBC says that, after chairing her final cabinet meeting at 9am, the outgoing prime minister will make a statement outside No.10 before travelling to Buckingham Palace for her final audience with the King.
This will be followed by Mr Sunak's first audience with the monarch, during which he will be invited to form a government.
He will then travel to Downing Street to make a statement at about 11:35am, before entering No 10.
Mr Sunak takes office as the third Conservative prime minister this year - prompting Labour to lead calls for an early general election as a result.
In the speech - which took place behind closed doors - Mr Sunak told them this was going to be a tough period and ruled out an early general election.
The former chancellor said the Conservative Party, trailing Labour in the polls by a huge margin, was facing an "existential threat", but could win the next election by uniting.
Serve with integrity
Later, in a TV address that lasted less than two minutes, Mr Sunak promised to serve with "integrity" and thanked outgoing Prime Minister Liz Truss for leading the country during "exceptionally difficult circumstances".
"The United Kingdom is a great country, but there is no doubt we face a profound economic challenge," he said. "We now need stability and unity and I will make it my utmost priority to bring our party and our country together."
There has been no shortage of guessing on who will be in Mr Sunak’s top team.
The Telegraph has been talking to insiders about the possible make-up of his Cabinet - and news on this could come as early as today. It is expected to be made up of "all the talents", and also mark the political return of the "adults". In other words - trusted ministerial deliverers. There has been speculation they could include Michael Gove.
Speculation also continues to mount on how Chancellor Jeremy Hunt plans to balance the books and calm the current economic turmoil.
He last week refused to rule out a fresh windfall tax on UK oil and gas producers. Labour and the Lib Dems have already called for another raid on the sector.
North Sea fiscal regime
But the North Sea industry is keen to stress to the new PM the need for a "sustainable and competitive" fiscal regime.
Deirdre Michie, chief executive of trade body Offshore Energies UK, said last night: "We look forward to meeting Mr Sunak and his team.
"When we do, we will be making a powerful case around the need for stability in the fiscal and regulatory regimes governing the UK's offshore sector.
“The UK needs to secure billions of pounds for offshore investments if it is to keep producing the gas, oil and offshore wind, plus other low-carbon energies, needed for future growth and productivity, and especially for the transition to net-zero.
"The scale and longevity of that investment means it is critical to establish a sustainable and competitive fiscal regime in the timeframe of this parliament, to secure the UK's energy future."