Shadow chancellor John McDonnell has remained defiant after he was criticised for branding Winston Churchill a "villain".
Theresa May joined ex-foreign secretary Boris Johnson in leading a chorus of criticism after the Labour heavyweight made the comment in reference to the the way Churchill dealt with striking Welsh miners while home secretary in 1910.
Churchill's decision to send troops to support police quelling riots in Tonypandy has long been a subject of historical debate.
Speaking to ITV News on Thursday, Mr McDonnell insisted there was more than one side to Churchill and said he welcomed the debate sparked by his comments.
In a question and answer session with the Politico website, Mr McDonnell was asked: "Winston Churchill, hero or villain?"
The shadow chancellor said: "Tonypandy – villain."
Churchill ordered 200 Metropolitan Police officers into Tonypandy, with a detachment of Lancashire Fusiliers held in reserve in Cardiff.
The soldiers were eventually called into the Rhondda Valley village to help deal with the situation.
The wartime leader, who was later knighted, was voted the greatest Briton in a BBC poll in 2002.
Ex-Foreign Secretary Mr Johnson, who has written extensively on Churchill, said Mr McDonnell should be "ashamed" of his remarks.
"Winston Churchill saved this country and the whole of Europe from a barbaric fascist and racist tyranny and our debt to him is incalculable," he tweeted.
"If John McDonnell had the slightest knowledge of history he would be aware that Churchill also had an extraordinary record as a social reformer who cared deeply for working people and their lives.
"JM should be utterly ashamed of his remarks and withdraw them forthwith."
Speaking to ITV News on Thursday, Mr McDonnell said that there was more than just one side to Churchill.
"In history, like many complex characters, Churchill has both sides to his him," Mr McDonnell said.
"A hero in the Second World War, but actually in many ways for working class families, not somebody they looked up to as a result of the actions when he was home secretary."
In response to his comments Theresa May’s official spokesman said the public will “reach its own judgment on this characterisation of Sir Winston Churchill”.
He noted that Churchill was voted history’s greatest Briton in a 2002 poll.
And he added: “The Prime Minister has quoted and referenced Sir Winston Churchill on many occasions and acknowledged him as one of the great prime ministers of the 20th century.
“She has a portrait of Sir Winston Churchill hung on the wall of her study in Number 10.
“His strong leadership, determination and unwavering personality inspired our country through our darkest hour and helped Britain protect those values of peace and freedom that we hold so dear today.”
Tory MP Sir Nicholas Soames, grandson of the former Conservative prime minister, told the Daily Telegraph: "Frankly it's a very foolish and stupid thing to say, surely said to gain publicity.
"I think my grandfather's reputation can withstand a publicity-seeking assault from a third-rate, Poundland Lenin. I don’t think it will shake the world."
Labour MP Ian Austin made it clear he disagreed with Mr McDonnell’s comments by posting a picture on social media of a figurine of the wartime leader he keeps at home.
Mr Austin tweeted: "Look who takes pride of place on my mantelpiece in Dudley: a real British hero, the greatest ever Briton, the man who motivated Britain to defeat the Nazis and fight not just for our liberty but the world’s freedom too."