Shadow Chancellor John McDonnell said Winston Churchill was a "villain" for his role in quelling riots in a city in southern Wales.
Asked whether the wartime British prime minister was a hero or a villain on Wednesday's event organized by Politico in London, McDonnell replied: "Villain – Tonypandy".
He referred to the Tonypandy incident in November 1910, when a miner was killed and around 580 people, including 80 policemen, were injured after Churchill, the then Home Secretary, sent 200 Metropolitan police to a reserve of Lancashire fusiliers in reserve Cardiff had to stop riots that broke out after the police attempted to break through the miners picket line.
The soldiers were finally used, although it was long disputed whether Churchill had personally endorsed the decision. Nevertheless, Churchill remained deeply unpopular in the valleys of South Wales and within the Labor Party.
In response to McDonnell's response, Churchill's grandson Sir Nicholas Soames said the Shadow Chancellor was seeking publicity and called him "Poundland Lenin."
"Honestly, it's a very silly and stupid thing to say to win publicity," he told The Daily Telegraph. "I think my grandfather's reputation can withstand a public relations attack emanating from a third-rate, Poundland Lenin. I do not think it will shake the world. "
The debate over the heritage of Churchill, who was named the largest Briton of all time in a BBC poll in 2002, has recently been renewed. Good morning Britain's host Piers Morgan condemned Green MEP Ross Greer on live television last month after politician Churchill had tweeted a "white supremacist mass murderer".
During the live interview with Politico London Playbook, McDonnell also acknowledged that it was unlikely that Labor would force a general election to renegotiate Brexit after Brexit shadow secretary Keir Starmer thought it was not a credible option.
"We still hope for general elections, but it's unlikely, so I think [Starmer was right]"McDonnell said.
In other remarks, the MP for Hayes and Harlington said that Theresa May was "on the run" and had predicted that Parliament would soon "resort [Brexit] from their hands "to give the government a gentler exit.
McDonnell said Labor's call for a permanent customs union could be the price to support the EU's resignation agreement.
Later, he warned, "Do not underestimate the strength of feeling to avoid a deal."