A radical leftist, who allegedly defended Stalin and North Korea, has been appointed to help lead the Labour Party’s general election campaign.

Andrew Murray, an aide to Unite Union leader Len McCluskey, only quit the Communist Party of Britain in December to join Labour. He also chaired the Stop the War Coalition for a decade – a role he handed over to, and then resumed from, Jeremy Corbyn in 2011 – which has been accused of supporting attacks on British troops.

A card-carrying member of the Communists since age 18, Mr. Murray has previously written articles commemorating genocidal Soviet tyrant Joseph Stalin and encouraging “solidarity” with North Korea. In a 2008 Morning Star article, Murray wrote about the “successes” of the Soviet Union.

In 1999, marking the 120th anniversary of the birth of Stalin, he said it was a moment to condemn Western powers behind the Hiroshima bomb and colonialism who “abominate the name of Stalin beyond all others. It was, after all, Stalin’s best-known critic, Nikita Khrushchev, who remarked in 1956 that ‘against imperialists, we are all Stalinists’.”

Proud to return as Stop the War Chair succeeding the new Labour Leader! — Andrew Murray (@apdmurray) September 19, 2015

Seventy years on, honour the heroes of the Red Army who saved Europe from a fate far far worse than David Cameron — Andrew Murray (@apdmurray) May 9, 2015

On North Korea, in 2003, he stressed: “Our Party [the Communists] has already made its basic position of solidarity with Peoples Korea clear.”

More recently, on the 2015 Islamist attack on the French satirical newspaper Charlie Hebdo, in which 12 people were slaughtered and 11 injured, Mr. Murray once again sought to divert blame onto the West. “The barbarism we condemn in Paris is minute compared to the barbarism wrought by imperialism across the planet in the last 13 years and we must condemn that,” he said.

Mr. Corbyn was quick to defend Mr. Murray Tuesday morning, who has been a close friend of the Labour leader for many years.

Speaking to reporters after addressing the Royal College of Nursing conference in Liverpool, Mr. Corbyn said: “Andrew Murray is a member of the Labour Party and he is an official at Unite, and he is temporarily helping us with the campaign.

“He is a person of enormous abilities and professionalism, and is the head of staff of Unite the union. To manage a very large union and a large number of staff takes special skills, and Andrew has them.”

Asked if he were worried about the allegedly “Stalinist” views of Mr. Murray, he replied: “I don’t believe that Andrew is anything other than a democratic socialist and member of the Labour Party like me.”

A spokesman for Mr. Corbyn said: “We don’t comment on staffing matters.”