Keir Starmer insisted he would carry on as British Prime Minister despite Labour suffering disastrous local election losses.
He acknowledged it had been a "tough" night for Labour but said that "days like this don't weaken my resolve to deliver the change that I promised".
Nigel Farage’s Reform UK made gains across the country as hundreds of Labour councillors were voted out, heaping pressure on the Prime Minister.
Mr Starmer faces further heavy losses as vote counting continues throughout today in both English local elections and contests for the Scottish Parliament and Welsh Senedd.
In Wales, Labour is expected to lose the national vote for the first time in more than a century while the SNP appears likely to remain the largest party in Scotland after 19 years in power.
Early results saw Labour haemorrhage hundreds of councillors and eight local authorities across England while Reform, the Greens and Liberal Democrats all made gains.
In Wales, Labour is expected to lose the national vote for the first time in more than a century while the SNP appears likely to remain the largest party in Scotland after 19 years in power.
Mr Starmer has already faced speculation about his leadership, with the Times of London reporting Energy Secretary Ed Miliband had urged the Prime Minister to set out a timetable for his departure.
But Deputy Prime Minister David Lammy urged his party not to play "pass the parcel" with the leadership in response to the election results.
Labour sources pointed to poor local election results under previous prime ministers, including Tony Blair who lost 1,100 councillors in 1999 but went on to win re-election in a landslide in 2001.
Meanwhile, Mr Farage hailed early results from yesterday's local election as a sign his party was on course for victory at a general election that is still up to three years away.
A jubilant Mr Farage heralded a "historic change in British politics," telling reporters "there is no more left-right" as his outfit was "scoring stunning percentages in traditional old Labour areas".
The Reform leader compared the substantial gains to clearing Becher's Brook, a famously difficult jump in the Grand National.
"If we cleared Becher’s Brook and landed well, we go on to win the Grand National.
"What is very clear to me is that our voters will stick with us now all the way through."
With 40 of the 136 councils declaring their full results in the early hours of Friday, Reform's gains reached 270 seats while Labour had lost more than 200.
Mr Farage’s party also took control of its first council of this set of contests, nabbing Newcastle-under-Lyme from the Conservatives.
Other key results included:
Reform UK won all 12 seats on offer in Hartlepool, pushing the formerly Labour-held council into no overall control.
Labour lost control of eight other authorities including Wandsworth, Westminster and Tameside, which includes Angela Rayner’s Greater Manchester constituency.
The Liberal Democrats appeared on course to record an eighth consecutive year of council gains, taking control of Stockport and Portsmouth, and becoming the only party on Richmond upon Thames Council, but lost their slender majority in Hull.
The Conservatives suffered yet more losses, but enjoyed some bright points, managing to regain Westminster from Labour and hold onto Harlow in Essex and Broxbourne in Hertfordshire.
The Green Party made modest gains in the early hours, but expected to improve significantly over the course of today as the party’s target councils in London declared their results.
Polling guru John Curtice said the results confirmed "the fracturing of British politics", telling the BBC that Reform was clearly ahead but still "probably not quite at 30% of the vote" while other parties were "just a little bit below 20%".
He suggested the results may not be as bad for Labour as some had predicted, saying the party could lose less than 1,500 seats.
Only about a fifth of the seats in the English Councils were counted overnight, but the results so far accord with expectations - a bad night for Prime Minster Keir Starmer's Labour party, and a good night for Nigel Farage’s Reform UK, which has won about a third of the seats declared so far.
With around a thousand seats filled by 7am this morning, Reform was leading with 327 seats, the Liberal Democrats were second on 237; Labour were third on 229 - a loss of 246 seats - the Conservatives were forth with 196 seats - having lost 122 - and the Greens were fifth with 48 seats. Independents had 40 seats.
Counting for most other council seats, and the Parliaments in Scotland and Wales begins at nine thirty this morning.
Pre-vote polling indicated the Scottish National Party will retain control of the Scottish Parliament, but will probably fall short of an overall majority, which had been seen as a pre-requisite for the SNP to renew its campaign for another referendum on Scottish independence.
But the biggest upset - and one with national implications - could happen in the Welsh Senedd, where a century of Labour domination in national elections, and 27 years of unbroken Labour rule in Cardiff could come to an end, with polls indicating the nationalist Plaid Cymru and Reform UK vying to be the biggest party.
