Keir Starmer resigns as UK prime minister, opening Labour contest

LONDON — Sir Keir Starmer announced on Monday that he will resign as leader of the Labour Party and as British prime minister, ending a turbulent two years in office and triggering a contest to choose the United Kingdom's seventh leader in a decade. Speaking outside 10 Downing Street, Starmer said he had lost the confidence of his own MPs and would step aside once his party has chosen a successor.

"Every decision I have taken has been about putting the country I love first," Starmer told supporters and journalists, adding that this was why he would resign. He will remain prime minister in a caretaker capacity until Labour completes its leadership election, which is expected to conclude in mid-July at the earliest.

The frontrunner to replace him is Andy Burnham, the former mayor of Greater Manchester, who returned to Parliament only days earlier and declared his candidacy within hours of Starmer's statement.

What triggered the resignation

Starmer's position became untenable after Burnham won the Makerfield by-election on 18 June with a majority of more than 9,000 votes, taking a seat vacated by Labour MP Josh Simons. The victory returned Burnham to the House of Commons and satisfied Labour's rule that leadership candidates must sit in the Parliamentary Labour Party, removing the final obstacle to a direct challenge.

The prime minister had been one of Britain's least popular leaders for months, with his net approval rating averaging around minus 46% by late 2025. The rebellion against him had been building since Wes Streeting resigned as health secretary in May. By 20 June, according to reports, Burnham had secured the backing of more than 200 Labour MPs. Streeting, once seen as Burnham's main rival, instead endorsed him.

Burnham paid tribute to the outgoing leader.

"Keir has given huge service to our country and I want to thank him for his leadership and dedication during such a challenging period," he said.

How Labour chooses a successor

Under Labour's rules, a candidate must be nominated by at least 20% of the parliamentary party — currently 81 MPs — to reach the ballot. The party has set out a compressed timetable:

• Nominations open on 9 July and close on 16 July.
• If only one candidate qualifies, that person becomes leader, and prime minister, on 17 July.
• If the race is contested, a ballot of party members would run through the summer, with a new leader due by 1 September.

With Streeting's withdrawal and Burnham's commanding support among MPs, an uncontested handover that installs him in Downing Street by mid-July is plausible, though other names — including Ed Miliband, Angela Rayner and Darren Jones — have circulated.

What it means for the EU — and Luxembourg

The change at the top immediately rippled into Brussels. A second post-Brexit UK-EU summit, scheduled for 22 July in the Belgian capital to finalise deals on trade, electricity-market integration and youth mobility, was thrown into doubt.

"We are re-assessing with (European Council) President Costa and the UK the opportunity of still holding the summit as had been announced last week and we will take it from here," said Paula Pinho, the European Commission's chief spokesperson.

The meeting was meant to build on the "reset" Starmer negotiated in May 2025, when London and Brussels agreed a new Strategic Partnership, a Security and Defence Partnership and common understandings on veterinary checks, linked carbon-trading schemes and a youth-experience programme. Those talks had stalled in November over UK access to the EU's joint defence-loans facility. Burnham is regarded in EU capitals as an unknown quantity, but he has spoken of wanting the UK back inside the trading bloc within his lifetime, and diplomats expect he could push for closer ties than his predecessor.

For Luxembourg, which hosts EU institutions including the Court of Justice and the European Investment Bank, the trajectory of UK-EU relations is followed closely. It also matters to the grand duchy's British residents. According to STATEC figures, 3,924 British nationals lived in Luxembourg at the start of 2023, down from about 5,786 in 2019 — a fall of roughly 30% since the Brexit referendum, partly because many naturalised as Luxembourgers. Closer cooperation on mobility, recognition of qualifications and travel would directly affect that community and the cross-border workers who move between the two jurisdictions.

For now, the immediate question is one of timing: whether Britain's next prime minister is in place soon enough to salvage a rescheduled Brussels summit, and how far a Burnham government would go in redrawing the post-Brexit settlement that Luxembourg and its partners have spent years rebuilding.