RISHI Sunak will become the UK's 57th Prime Minister after Tory MPs backed the former chancellor to take the keys to Number 10.

Following the resignation of Liz Truss, MPs were gunning for nominations from fellow parliamentarians over the weekend.

But just ahead of the announcement, Penny Mordaunt pulled out of the race leading to Sunak winning automatically. 

Following the result, the SNP reiterated calls for a General Election and accused the Tory party of "running scared of democracy", while his predecessor Truss said Sunak had her full support. 

We previously told how Sir Graham Brady, chair of the backbench Tory 1922 committee, revealed just hours after Truss’s resignation on Thursday October 20 that any candidate standing to be the next PM needed to reach 100 nominations amongst the parliamentary party.

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With 365 Tory MPs currently holding seats, this meant that there could only be a maximum of three candidates in a bid to whittle down any “serious” contenders quicker. 

In the summer contest, which Truss won over Sunak, there were nine MPs in the running at the beginning of the race.

As Mordaunt pulled out of the latest contest just before 2pm, Sunak was appointed automatically, with a formal audience with King Charles to follow to make it official. 

A source for the Penny Mordaunt campaign said the Commons Leader got the backing of 90 MPs.

They told the PA news agency: “1922 has offered to verify the numbers but Penny got 90. She is fully backing Rishi.”

Brady told a meeting of the 1922 committee that only Sunak had reached the threshold for nominations and would address the party at 2.30pm.

Entering the room to the noise of MPs banging on desks, Brady said: "As returning officer in the leadership election, I can confirm that we have received one valid nomination."

Talking over cheers from MPs, he added: "Rishi Sunak is therefore elected as leader of the Conservatives.

"You may wish to know the new leader of the party will address us this room and at half past two."

On Twitter, Mordaunt wrote: "These are unprecedented times. Despite the compressed timetable for the leadership contest it is clear that colleagues feel we need certainty today.

"They have taken this decision in good faith for the good of the country.

"Members should know that this has been fairly and thoroughly tested by the agreed 1922 process.

"As a result, we have now chosen our next Prime Minister. This decision is an historic one and shows, once again, the diversity and talent of our party. Rishi has my full support."

The National: Ross gave his support to Sunak after the announcement was madeRoss gave his support to Sunak after the announcement was made

Scotland reacts as Rishi Sunak set to become PM

Meanwhile, Scottish Tory leader Douglas Ross released a statement which said: “I’d like to congratulate Rishi Sunak on becoming the new Conservative Party leader and prime minister, and look forward to working with him for the good of Scotland and the whole United Kingdom.

“Our country – like others around the world – faces tough economic challenges. Against that backdrop, it’s important that we have someone at the helm with a proven track record in running the nation’s finances, who can provide economic stability and reassurance to the markets.

“Recent weeks have been difficult and unsettling for both the Conservative Party and, more importantly, the country. Now all our focus must be on bringing the nation together and navigating the tough economic conditions we face.

“As he showed during his time as chancellor – not least in safeguarding one in three Scottish jobs during the pandemic through the furlough scheme – Rishi Sunak is uniquely well equipped for that task.”

In a statement released later on Monday, Scottish Secretary Alister Jack said: “Congratulations to Rishi Sunak, I wish him the very best in the job and offer him my wholehearted support. I urge the Conservative Party to come together behind our new Prime Minister.

“We are facing very significant challenges at home and abroad, and there is much to be done. We need to unite and focus on delivering for everyone in our country.”

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Speaking after Sunak's win was announced, SNP Westminster Leader Ian Blackford MP said: "The Tories cannot be allowed to impose a third Prime Minister without a general election - voters must get a say and the SNP is determined to ensure they do.

"The Tory government had no mandate to trash the UK economy with its disastrous budget. And it has no mandate to install yet another leader who will impose devastating austerity cuts - making households pay through their teeth for Tory mistakes.

"No one voted for this. The only reason the Tories are running scared of democracy is because they fear the verdict of the people. There's no better indication of that than the polling in Scotland, which shows voting SNP could wipe the Tories out completely.

"The decisions that are made in the weeks and months ahead will be hugely significant and will impact the economy, public services and household budgets for years to come. Voters must get a say on what course they want to take - instead of having damaging decisions imposed against our will.

The National: Blackford reiterated the SNP's calls for a General ElectionBlackford reiterated the SNP's calls for a General Election (Image: Web)

"The SNP will continue to put maximum pressure on Tory MPs to hold an election. And, I've written to Keir Starmer making clear SNP MPs will back a vote of no confidence in the Tory government, if he tables one this week.

"The Tory economic crisis and constant chaos at Westminster shows exactly why Scotland needs independence, so we can get rid of Westminster Tory governments for good."

Scottish Greens co-leader Patrick Harvie said the announcement would be "music to the ears of his super rich friends" but "devastating" for everyone else.

He added: "The last thing we need is yet another multi-millionaire Tory Prime Minister looking the other way while millions suffer and attacking the services that we all rely on.

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“In 2014, we were told that a No vote was the only way to secure our economic stability. Since then we have had four Prime Ministers, each of them even worse than the one before. Rishi Sunak will be the fifth. 

“Scotland didn’t vote for any of them. There is no doubt that we need an election, and the chance to remove this chaotic government. But we also need a fair and democratic referendum. 

“Surely after all this, nobody can doubt that Scotland is capable of better than the shambles that calls itself the UK Government.”

Roz Foyer, Scottish Trade Union Congress (STUC) general secretary, said: "A sinking ship has just appointed a new captain. No Tory Prime Minister - least of all one of the richest men in the country - has a clue about the Tory-charged economic devastation facing working people across Scotland.

"We need a general election and we need it now."

What are UK opposition parties saying about Sunak's win?

Angela Rayner, Labour's deputy leader, blasted the Tories for appointing the former chancellor without him "saying a single word about how he would run the country".

She added: “This is the same Rishi Sunak who as Chancellor failed to grow the economy, failed to get a grip on inflation, and failed to help families with the Tory cost of living crisis.

“And it’s the same Rishi Sunak whose family avoided paying tax in this country before he put up taxes on everyone else.

“With his record - and after Liz Truss comprehensively beat him over the summer - it’s no wonder he is dodging scrutiny.

“Rishi Sunak has no mandate and no idea what working people need. We need a general election so the public get a say on the future of Britain – and the chance for a fresh start with Labour.”

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Ed Davey, the UK Lib Dem leader, accused the Tories of installing “another out-of-touch prime minister” and also backed calls for a General Election.

He said: “Rishi Sunak has shown time and time again that he doesn’t understand the challenges facing struggling families and pensioners, whether it’s paying their heating bills this winter or waiting weeks to see a GP or dentist.

“We will now see more of the same, as Conservative MPs plot and squabble amongst themselves while completely ignoring the huge challenges facing the country. The only way to end the chaos is a general election now.”

Truss, the outgoing PM, wrote a short note of congratulations to her successor on Twitter.

She said: "Congratulations @RishiSunak on being appointed as Leader of the Conservative Party and our next Prime Minister. You have my full support."

The National: Johnson's reported comeback did not come to fruitionJohnson's reported comeback did not come to fruition

Rumours swirled over the weekend that Boris Johnson, who was forced to resign after mounting scandals and his inability to handle harassment complaints amongst his party, would look to enter the race.

He claimed he had 102 MPs backing him, but then pulled out of the running late on Sunday night, causing many newspapers to hastily re-write their front pages.

Despite Sunak’s win, the Tory party is currently embroiled in a civil war, with many MPs including former culture secretary Nadine Dorries demanding a General Election despite the predicted electoral wipeout on the cards for the governing party.