Keir Starmer has been named as the new leader of the British Labour party.
The shadow Brexit secretary replaces Jeremy Corbyn, who had led the party since 2015.
The contest was launched after Mr Corbyn announced he was stepping down following the party's largest UK election defeat since 1935 in December.
Two other candidates - Rebecca Long-Bailey and Lisa Nandy - had also made the final ballot.
Angela Rayner, meanwhile, has been named as the party's new deputy leader.
Congratulations to @Keir_Starmer, the new Leader of the Labour Party!#LabourLeadership pic.twitter.com/i2PjxXaWMf
— The Labour Party (@UKLabour) April 4, 2020
Following the announcement of the results, Mr Starmer said: "It’s the honour and privilege of my life to be elected as Leader of the Labour Party.
"I will lead this great party into a new era, with confidence and hope, so that when the time comes, we can serve our country again – in government."
He also praised the outgoing leader Jeremy Corbyn, saying he had led the party through some "very difficult times" and "energised" the Labour movement.
The left-wing Momentum group - which had played a key role during Mr Corbyn's leadership and backed Mrs Long-Bailey to succeed him - congratulated Mr Starmer and Mrs Rayner on the results.
Congratulations to @Keir_Starmer and @AngelaRayner on their election as leader and deputy. We look forward to working with you both to elect a Labour government that will carry out the kind of transformational policies our country needs. 1/8
— Momentum 🌹 (@PeoplesMomentum) April 4, 2020
They said: "[Mr Starmer's] mandate is to build on Jeremy’s transformative vision, and this means appointing a broad shadow cabinet who believe in the policies and will work with members to make them a reality.
"We’ll hold Keir to account and make sure he keeps his promises, champion big ideas like the Green New Deal, build the power of Labour members and do everything we can to get a Labour government elected."
In a Facebook post yesterday ahead of the final leadership results, Mr Corbyn said last year's election was a 'Brexit election' and the party had failed to bridge the gap between Leave and Remain voters.
However, he pledged: "I will continue to campaign on the issues and principles that have motivated me as Leader, as an MP, as a councillor and as a party member for more than 50 years.
"I can assure you my voice will not be stilled. I’ll be out there campaigning for socialism, peace and justice, and I feel sure we’ll be doing that together."
The UK Labour leadership results come only hours after Alan Kelly was named as the new leader of the Irish Labour party.