Keir Starmer officially took office as the UK’s new prime minister on Friday, following his centre-left Labour Party’s decisive victory in the general election, ending 14 years of Conservative rule.

Head of State King Charles III appointed Starmer during a meeting at Buckingham Palace, marking the 61-year-old former human rights lawyer’s ascension to the role of prime minister.

Amid cheers from Labour supporters lining Downing Street, Starmer arrived as the party’s first prime minister since Gordon Brown in 2010.

In his inaugural speech, he declared, “Our country has voted decisively for change, for national renewal, and a return of politics to public service. The work of change begins immediately, but rest assured, we will rebuild Britain.”

Meanwhile, a sombre Rishi Sunak conceded defeat as his Conservatives suffered significant losses, including at least 12 senior Cabinet members and his predecessor Liz Truss. Sunak, apologizing to the public before leaving Downing Street for the final time as prime minister, announced his intention to step down as Tory leader once a successor is chosen.

Labour secured a commanding majority in the House of Commons, surpassing the 326 seats required for an overall majority with 412 seats won as of 1200 GMT on Friday.

The Conservatives, facing a record-low result of 121 seats, saw their support divided by Nigel Farage’s Reform UK party. In another shift, the Liberal Democrats overtook the Scottish National Party as the third-largest party.

International leaders reacted positively to Starmer’s victory, with congratulations pouring in from European Council chief Charles Michel, French President Emmanuel Macron, and German Chancellor Olaf Scholz, who praised Starmer as a prospective “very good, very successful” prime minister.

Ukrainian President Volodymyr Zelensky affirmed their nations’ continued alliance, while citizens like engagement officer Ramsey Sargent expressed optimism about the future under Starmer’s leadership.

The election results diverged from trends among Britain’s Western allies, where the far right in France and the potential returns of leaders like Donald Trump in the United States contrasted with the UK’s centrist shift.