Lee Anderson shot down suggestions Reform only won the Runcorn and Helsby by-election because Labour has failed to criticise Donald Trump’s talk of making Canada the 51st US state. Reform’s Sarah Pochin won the Cheshire seat last week by six votes in an extraordinarily close race with Labour.

Mr Anderson, Reform chief whip and MP for Ashfield, rejected the claims as he suggested it wasn’t an important topic for voters. In a seven-word slap down shared on social media, the former deputy chair of the Conservative party said: “Because Canada came up on every doorstep.” He was responding to a post by Observer columnist Will Hutton who argued Labour’s narrow defeat in Runcorn and Helsby could have been avoided.

“If Starmer had called out Trump for wanting to annex Canada, challenged Farage to do the same ( which he would have ducked) Labour would have held Runcorn,” he wrote on X, formerly Twitter.

“Politics is about definition and mission. Farage has it. So could Labour.”

The by-election, the closest since records began in 1945, was one of a number of disappointments for Labour last week after Reform made significant gains in the local elections across England.

Nigel Farage’s party gained more than 600 seats and took control of 10 local authorities in the elections.

He claimed the results marked “the end of two-party politics” and the “beginning of the end of the Conservative Party”, with the Tories also suffering heavy losses.

Ms Pochin was sworn into parliament on Tuesday after overturning a huge Labour majority of more than 14,000.

The by-election in Runcorn and Helsby was triggered when former Labour MP Mike Amesbury quit after admitting punching a constituent.

The Prime Minister said Labour’s loss to Reform in the historically safe seat was “disappointing” but said he was determined to go “further and faster” in delivering change.

He has insisted there will be “no change” to the Government's winter fuel payment cut despite calls to soften the blow following the disastrous local election results.

Sir Keir was said to be considering a partial U-turn on winter fuel payment cuts after Labour lost 187 council seats.

Ministers fear the changes, which the Government admits will plunge 100,000 pensioners into poverty, have turned voters against the party and could cost it victory at the next general election.