London (AFP) - Britain’s incoming prime minister Rishi Sunak vowed Monday to bring “stability and unity” at a time of economic crisis, after he was named the beleaguered Conservatives’ new leader.

Sunak, 42, a Hindu, will be the UK’s first prime minister of colour following the implosion of Liz Truss’s premiership after just 44 days.

Truss will hold a final cabinet meeting on Tuesday morning before submitting her resignation to King Charles III, who will then appoint Sunak as PM, Downing Street said.

The new leader will make his first remarks to the nation from outside Number 10 around 11:35 am (1035 GMT).

Sunak prevailed after Penny Mordaunt, the last rival left in the party’s leadership race after Boris Johnson dramatically dropped out, failed to secure enough nominations from fellow Tory MPs.

Both Mordaunt and Truss pledged their full support.

However, there was public silence from Johnson – even as Sunak urged his warring party to “unite or die”, according to Tory MPs present in a closed-doors meeting.

Addressing the public for the first time, the new leader said Britain faced “a profound economic challenge”.

“We now need stability and unity and I will make it my utmost priority to bring our party and our country together,” he added.

World leaders, including Indian Prime Minister Narendra Modi, congratulated the latest UK leader.

Irish Prime Minister Micheal Martin said he welcomed jointly tackling “important issues we face on these islands” while European Council Charles Michel noted “working together is the only way to face common challenges”.

- ‘Significant moment’ -

Just seven weeks after he lost out to Truss following Johnson’s own removal from office, Sunak pulled off a stunning reversal in fortunes. He is now vowing to do the same for Britain on a platform of fiscal responsibility.

But 62 percent of voters want a national election before the end of the year, pollster Ipsos said.

Another poll by YouGov said opposition Labour leader Keir Starmer was favoured as the “best prime minister” in 389 parliamentary constituencies – while Sunak was favoured in 127.

Scottish leader Nicola Sturgeon, whose nationalist government in Edinburgh wants to hold an independence referendum next year, congratulated Sunak “notwithstanding our political differences”.

“That he becomes the first British Asian – indeed the first from any minority ethnic background – to become PM is a genuinely significant moment,” she said.

The contest, triggered by Truss’s resignation on Thursday, had required candidates to secure the support of at least 100 Conservative MPs by 2:00 pm (1300 GMT) on Monday.

Only Sunak made the threshold, putting an abrupt end to the contest.

The wealthy descendant of immigrants from India and East Africa, he had crossed that threshold by Friday night, and amassed nearly 200 public nominations – more than half the parliamentary Tory party.

Johnson’s withdrew from the race before he had even formally announced his candidacy.

Sunak’s victory came on the day Hindus worldwide mark the start of the five-day festival of Diwali – a celebration of the victory of good over evil.

When he was chancellor of the exchequer, in November 2020, Sunak marked the occasion by lighting oil lamps on the front step of the chancellor’s official residence at 11 Downing Street.

- ‘Not the right time’ -

The Tories were forced into their second leadership contest since the summer due to Truss’s resignation following a disastrous market response to her tax-slashing budget plans.

Johnson cut short a Caribbean holiday to return to Britain on Saturday and attempt an immediate return to Downing Street, promptly dividing the ruling Conservatives.

Critical backbench MPs warned of resignations id he became party leader again, which might have led to a general election. One is not due for at least two years.

In a sign of his diminished political standing, Johnson swiftly conceded late Sunday, admitting “you can’t govern effectively unless you have a united party in parliament”.

“I believe I have much to offer but I am afraid that this is simply not the right time,” he said, while insisting he had secured the 100 nominations needed to progress.

Sunak was quick to pay tribute to Johnson, tweeting: “I truly hope he continues to contribute to public life at home and abroad.”

Labour leaders said Sunak must face the country.

“The Tories have crowned Rishi Sunak without him saying a word about what he would do as PM. He has no mandate, no answers and no ideas,” tweeted Angela Rayner, deputy Labour leader.