London — When Keir Starmer was elected to lead Britain's Labour Party in 2020, right after the party suffered its worst general election defeat in 85 years, he made it his mission to make the party electable again. Four years later, after 14 years of governments led by the rival Conservative Party, Starmer arrived Friday at the prime minister's residence at 10 Downing Street for the first time as the man in Britain's top job.

With all but two of the final results in, Labour had won a remarkable 412 of the seats in the British Parliament's 650-seat House of Commons. The Conservatives held only 121, a massive hemorrhaging of support for the party that swept the last election in 2019.

Former Prime Minister Rishi Sunak conceded early Friday morning, saying voters had delivered a "sobering verdict" on his Conservative Party, and he quickly headed to Buckingham Palace and submitted his resignation to King Charles III.

Starmer, 61, has faced years of criticism for a perceived lack of charisma, but his methodical mission to drag Labour back toward the center of British politics and broaden its voter appeal paid off. Starmer and Labour also, indisputably, capitalized on years of economic pain and political chaos under the Conservatives.

Starmer takes the reins of government with a herculean task at hand, with the British people's overall trust in politicians at rock bottom, a record number of children in the U.K. living in poverty, and both his party and the Conservatives grappling with how to handle surging support for a far-right, anti-immigrant strain of politics taking root across Europe.

What happens now?

Starmer became the new British prime minister with the ballots from the final two races still being tallied Friday morning.

Sunak emerged from the prime minister's official residence at 10 Downing Street in London, which he inhabited for only 14 months, and gave a statement confirming that he would go immediately to meet with King Charles to formally offer his resignation. He offered an apology to the British people and said he had "heard your anger," taking personal responsibility for his party's massive loss.

Starmer met the king at Buckingham Palace right after Sunak, and the monarch took the constitutionally necessary but largely ceremonial step of inviting the Labour Party leader to form a new government, confirming Starmer's role as the new prime minister. Starmer left the palace and headed straight to Downing Street to give his first public address as the country's leader. 

"I want to thank the outgoing prime minsiter Rishi Sunak," Starmer said, paying tribute to his predecessor as the first Asian leader of Britain. 

Starmer declared it a "day of renewal," and a "return of politics to public service."

"We need to move forward together," he said, acknowledging the huge lack of trust in politics in the country generally and saying it can "only be healed by actions, not words. I know that, but we can make a start today." 

"My government will serve you," he said, promising to show that "politics can be a force for good," by putting "country first, party second."

Once the formalities were completed, Starmer quickly set to work. A steady stream of top Labour Party members walked up to enter 10 Downing Street, believed to be heading in to learn of their appointments to Starmer's new cabinet. The new prime minister will also receive briefings from key members of the civil service and the intelligence community and start taking phone calls from world leaders.

He promised to get down to the often unglamorous business of running the country, bringing the change he campaigned on, without delay.

Where does Keir Starmer come from?

Prime Minister Sir Keir Starmer — the former lawyer was knighted for services to criminal justice — has, through years of chaos (you may remember Partygate, or perhaps even Prime Minister Liz Truss' fewer than 50 days in power) projected an almost dull managerialism that appears to have become a beacon for a welcome return to political normalcy. 

Starmer grew up in a small town in Surrey, just outside London. His mother worked for the National Health Service, Britain's free public health care system, and his father was a toolmaker — a fact that Starmer repeated so often during the election campaign that it became a meme.

His mother suffered for all her life from Still's disease, a type of inflammatory arthritis, and died only a few weeks after he was first elected to the British Parliament in 2015. His father died three years later. Starmer has said his relationship with his father was strained, and that never telling him, "I love you and I respect you" is "the one thing I do regret."

Starmer was the first member of his family to go to university, after which he helped run a left-wing magazine called Socialist Alternatives. He then became a lawyer, rising up the ranks to become the head of public prosecutions in 2008, running the British government's Crown Prosecution Service. He received his knighthood in 2014, the year before he turned to politics.

Despite his legitimate background in tackling serious crime, Starmer has never managed to shake the image of a relatively boring politician. He's even leaned into it on occasion.

"If, in the end, that is the only bit of mud left to sling, then I'm pretty comfortable," he told Britain's ITV in January. "If they are calling you boring, you're winning."

What are Keir Starmer's policies?

Throughout his tenure as Labour leader, Starmer has tried to make his party more electable by forcing out individuals seen as entrenched in its socialist left wing — the faction that ran the party under its previous leader, Jeremy Corbyn (whose cabinet Starmer served in, incidentally). 

After Corbyn called the findings of an inquiry into antisemitism in the party "dramatically overstated," Starmer suspended him. 

"Sometimes you have to be ruthless to be a good leader," Starmer told Esquire about the episode. 

His public mantra has been "country before party."

Starmer's move toward centrism has been criticized by left-leaning members of his own party and others. He irked many by backtracking on several key pledges, including that Labour would increase income tax, scrap university tuition fees and nationalize the majority of Britain's public services.

He has also come under fire for Labour's screeching u-turn on a green investment pledge worth more than $35 billion annually, and for equivocating on alleged Israeli war crimes in Gaza, despite his legal background.

In a recent speech, Starmer said he had a long-term "big, bold plan" for Britain. But he cautioned that "we need first steps." 

Those, according to the BBC, include clamping down on tax avoidance, shortening NHS patient waiting lists and recruiting more teachers and neighborhood police officers. He also wants to negotiate a better deal with the European Union, given the catastrophic economic consequences of the U.K.'s "Brexit." 

He called his unflashy election pledges a "down payment" on what the Labour Party can offer Britain if it is given enough time.

"I'm not going to make a promise before the election that I'm not comfortable we can actually deliver," he stressed.

"A lot of people on the left will accuse him of letting them down, betraying socialist principles. And a lot of people on the right accuse him of flip-flopping," Tim Bale, a political scientist at Queen Mary University of London, told The Associated Press. "But, hey, if that's what it takes to win, then I think that tells you something about Starmer's character. He will do whatever it takes — and has done whatever it takes — to get into government."

How might Starmer influence U.S.-U.K. relations?

With British and American election cycles coinciding for the first time since 1992, there's a lot of uncertainty about how U.S.-U.K. relations could look by the end of the year. 

Starmer has spoken admiringly of President Biden, particularly his focus on job creation and investment in domestic industry. The Economist even described him as "infatuated" with the American president. 

Senior Labour figures reportedly met secretly with Democratic counterparts even before election day.

So, it's expected that Mr. Biden will have a close ally in Starmer — if Mr. Biden is still the president in 2025.

If former President Donald Trump wins in November, U.S.-U.K. relations would likely be less chummy. 

Despite her being a Conservative and thus ostensibly on the same side of the political aisle, Trump had a difficult relationship with former Prime Minister Theresa May during his first term in office. He got on better with the more populist — and many say more Trumpian — Boris Johnson. 

"A Biden White House would find Starmer a well-wisher and useful spear-carrier," Eliot Wilson, a former senior official in the U.K. House of Commons wrote in The Hill. "For Trump, he would prove a vague annoyance, and could not be counted on to echo the wilder MAGA phrasebook."

The reality for U.K. leaders, from any party, almost a decade after Britain's exit from the EU, is that the long-touted "special relationship" with Washington has never been more vital.

"We will work with whoever is elected," Starmer has said. "We have a special relationship with the U.S. that transcends whoever the president is."

In:
• Rishi Sunak
• Conservative Party
• Brexit
• Britain
• Politics
• Keir Starmer
• Election
• United Kingdom
• Labour Party

Frank Andrews

Frank Andrews is a CBS News journalist based in London.

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