Rishi Sunak has suffered a double blow after losing both the Kingswood and Wellingborough by-elections.

Labour overturned majorities of 11,220 and 18,540, delivering the Government’s ninth and tenth by-election defeats of the current Parliament and securing its second largest swing from the Conservatives ever.

Gen Kitchen secured Wellingborough with 45.8% of the vote, while Damien Egan won Kingswood with 44.9% of the vote.

The results provided Labour with a boost after a U-turn on the party’s pledge to spend £28 billion on green projects and an antisemitism row that forced it to drop its candidate for another by-election in Rochdale in two weeks’ time.

The twin defeat piles more pressure on the Prime Minister following the news that the UK entered a recession at the end of 2023, while Reform UK scored its best by-election results after targeting disgruntled voters on the right, securing more than 10% of the vote for the first time in a by-election.

Reform deputy leader Ben Habib won 13% of the vote in Wellingborough, while Rupert Lowe won 10% in Kingswood.

The results also mean the Government has now suffered the most by-election defeats of any government since the 1960s, surpassing the eight defeats suffered by John Major in the run-up to Tony Blair’s 1997 landslide victory.

Labour leader Sir Keir Starmer hailed the victories, saying: “These are fantastic results in Kingswood and Wellingborough that show people want change and are ready to put their faith in a changed Labour Party to deliver it.

“By winning in these Tory strongholds, we can confidently say that Labour is back in the service of working people and we will work tirelessly to deliver for them.

“The Tories have failed. Rishi’s recession proves that. That’s why we’ve seen so many former Conservative voters switching directly to this changed Labour Party.

“Those who gave us their trust in Kingswood and Wellingborough, and those considering doing so, can be safe in the knowledge that we will spend every day working to get Britain’s future back.”

In Wellingborough, the result announced at 4am showed Gen Kitchen, who cut short her honeymoon to campaign in the by-election, saw a Tory majority of more than 18,000 turn into a Labour majority of 6,436.

The swing of 28.5% is the largest from the Conservatives to Labour since the 1994 Dudley West by-election, where a 29.1% swing presaged Tony Blair’s landslide victory three years later.

Ms Kitchen said: “The people of Wellingborough have spoken for Britain. This is a stunning victory for the Labour Party and must send a message from Northamptonshire to Downing Street.”

In Kingswood, where the result was announced shortly before 2am, Labour’s Damien Egan defeated Conservative Sam Bromiley, securing 11,176 votes and a majority of 2,501.

In his victory speech, Mr Egan thanked the activists that helped him win and the people of Kingswood for putting their trust in him.

He said: “It’s a trust that I promise to repay, to show you that politics can be different and it can make difference.

“In Kingswood, as across the country, 14 years of Conservative government have sucked the hope out of our country with a feeling that no matter how hard you work, you just can’t move forward.

“And with Rishi’s recession we’re left again paying more and getting less. It doesn’t have to be this way, you know it, I know it, we all know it.

“When the Prime Minister finally finds the courage to give the people a say, we’re going to need each and every one of you again to come out and vote and make sure your voices are heard.”

Defeated Conservative candidate Sam Bromiley left the count as soon as Mr Egan had finished speaking, declining to comment to reporters.

The defeats mean the Conservatives have suffered more by-election losses in this Parliament than any previous government since the 1960s, surpassing the eight defeats experienced by John Major between 1992 and 1997.

But senior Conservative MP Sir Jacob Rees-Mogg sought to play down the importance of the results for predicting what will happen at the general election.

He told PA: “By-elections are an opportunity for people not to turn out, to protest and at ensuing general elections they don’t give a consistent guide to what happens.”

Sir Jacob acknowledged the Tories would need to “learn” from the results, saying: “Conservative Party votes are most likely to come from people who stay at home or who voted Reform.

“How do we win them back to the Tory family? People who share many views and values with us.

“By delivering things they believe in and that means lower taxation, taking more of the advantages of Brexit, with more of the removal of EU retained law, it means doing less on the green issue that is making people cold and poor, and helping revitalise our economy.”