Theresa May’s Conservatives gained more than 550 council seats and swept to shock victories in mayoralty contests in the West Midlands and Tees Valley in results that placed her party on track to secure a thumping majority in the general election.



The prime minister insisted she was not taking “anything for granted” but the Tories enjoyed a stunning day that was matched by a dramatic decline for Jeremy Corbyn’s Labour party, which lost more than 300 seats.

The results forced Labour to hand over control of a series of English councils including Derbyshire, Nottinghamshire and Northumberland, while in Scotland the party lost its grip on Glasgow for the first time in 40 years. Paul Nuttall’s Ukip was crushed as every single councillor facing election suffered defeat.



The results were turned into a projected national vote share of 38% for the Tories, 27% for Labour and 18% for the Lib Dems, with Ukip plunging to just 5%. Although that prediction is narrower than the polls, it projects that May would win a solid majority in June’s general election.



Despite the scale of the Conservative victory, May told reporters that she still believed Labour could win the general election. Speaking after a visit to a factory in Brentford, west London, where the Tories are hoping to overturn a Labour majority of just 465, the prime minister said: “The reality is that, despite the evident will of the British people, we have bureaucrats in Europe who are questioning our resolve to get the right deal. Only a general election vote for the Conservatives will strengthen my hand to get the best deal on Brexit.”

Her party is also preparing to launch its flagship health policies over the weekend, with the health secretary, Jeremy Hunt, scheduled to appear on television on Sunday.

Corbyn issued a statement acknowledging some of the problems Labour faced: “The results were mixed. We lost seats but we are closing the gap on the Conservatives.” He insisted that Labour could still win the general election, though admitted it was an “challenge on an historic scale”.



He said he was “utterly determined” to use every hour of the next four weeks to get his message across. “We’ve now got five weeks to get a message out there.”

Labour’s consolation was two convincing victories in the north-west in which Andy Burnham and Steve Rotheram were elected as metro mayors for Manchester and Liverpool.



In Scotland, the SNP made modest gains, although there was also a surge for the Conservatives. The Lib Dems lost dozens of seats in England but saw a boost in their overall vote share.



Labour had a mixed night in Wales losing some important councils, including Blaenau Gwent and Bridgend, where the prime minister recently visited to boost the chances of a Tory candidate becoming MP. But Labour held seven councils including Cardiff, Swansea and Newport.

May’s claim that the EU was meddling in British affairs, which propelled her on to the front page of every national newspaper on Thursday morning as voters headed to the polls, was believed to have contributed to her party’s success against Ukip.

Paul Nuttall’s Ukip lost every council seat it was defending. Photograph: Nick Ansell/PA

The results suggest Nuttall’s party could be wiped out after it won one new seat but lost every one it was defending, including being crushed in Brexit-supporting areas such as Essex and Lincolnshire, where the leader is fighting to become an MP.

Nuttall claimed that, if his party’s hammering was down to a Tory advance driven by May’s determination to leave the EU, then it was a price he was “prepared to pay”.

The former Ukip MP Douglas Carswell, who defected from the Conservatives, said it was “over” for a party that once soared to overall victory in European elections in 2014 and secured 4m votes in a general election under the stewardship of Nigel Farage.

What is a metro mayor? A metro mayor is the chair of a combined authority – made up of several local authorities – that has agreed on a devolution deal with central government.



Unlike city mayors, who head a single city council or local authority, metro mayors have powers to make decisions across the whole city region.



While city mayors are responsible for public service delivery (such as schools, recreational facilities and fire services), metro mayors will be responsible for setting out a strategy for economic growth in their region, and have certain powers over issues such as housing, transport and skills.



The exact function of the metro mayors will depend on the details of the devolution deal reached with central government. Greater Manchester, for example, will have more powers over criminal justice, and health and social care.



Metro mayors will work with the leaders of their local authorities to create a strategy for the wider area. They will also be able to lobby local MPs on policy matters that relate to their area.



They will chair a combined authority cabinet, made up of the leaders from each local authority, who can reject the metro mayor’s strategy with a two-thirds majority vote.



The role of the metro mayor can also be merged with that of the police and crime commissioner, but the two positions can be kept separate.

Political analysts have argued that Ukip had become a “gateway drug” for voters in Labour heartlands to shift to the Tories, which could be hugely damaging for Corbyn’s party. Commentators highlighted dozens of Labour seats where the Ukip vote is larger than the party’s majority.

One of the biggest blows for Labour was to watch the former John Lewis boss Andy Street narrowly win the West Midlands mayoralty for the Conservatives, in a sign that May could be making inroads into traditional Labour strongholds. He claimed to have won by reaching out to new voters with a “moderate, tolerant, inclusive” local plan but added that the question of leadership had been a huge boost for the Tories.

Many Labour candidates said they were planning to run local campaigns without a focus on Corbyn, claiming he had been toxic on the doorstep. Stephen Kinnock, who is contesting the seat of Aberavon, said the results amounted to a “disastrous picture” and Corbyn’s leadership had come up as an issue on the doorstep.

Siôn Simon, Labour’s losing candidate in the West Midlands, said: “We can’t duck the reality of what we heard in the places we won on the streets of cities and towns like Birmingham, Coventry, Wolverhampton and Sandwell.

“Traditional working-class voters, who we were born to serve, quite simply want to hear a clearer, stronger message about traditional values like patriotism, hard work and a defence of decency, law and order.”

Alan Rhodes, who was the Labour leader of Nottinghamshire county council but is now leader of the opposition group, admitted that his party was “in a difficult place at the moment”. He made clear that he believed the national polls had resulted in his group losing control.

“This doesn’t reflect on our four years in office locally. It is more reflective of the national malaise that the party finds itself in. I’m proud of what we’ve delivered and achieved in our four-year term – Labour councillors should be proud of that,” he said.