Andrew Murray, who succeeded Jeremy Corbyn as the chair of the Stop the War coalition, made the horrific jibe in 2013 when the royal was serving with the Army Air Corps in the war-torn country.
In a speech at a Stop the War rally in February 2013, former Communist party member Mr Murray said: “There’s the war on Afghanistan where we have to campaign to bring all our troops home now.
Mr Murray has been forced to apologise for the sick jibe
“I mean I suppose we could offer to leave Prince Harry if that would help?
“Otherwise all the troops must be brought home now.”
After he was confronted about the jibe, Mr Murray told the Sun he was sorry for the “flippant remark in poor taste”.
Prince Harry in pictures Tue, March 21, 2017
Prince Harry royal visits around the world and a mixture of all the charitable work he's done.
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Prince Harry during a visit to Hamilton College on March 21, 2017 in Leicester
He added: “I was delighted that Prince Harry returned home safely and, as I said in my speech, I only ever wanted our troops to return home safely from that conflict.”
Mr Murray’s initial comments came despite the fact that a British soldier was abducted and killed in Helmand Province in 2011.
Prince Harry had been deployed in Afghanistan for 20 weeks between late 2012 and early 2013.
Despite Mr Murray’s apology, some senior Tories have urged Jeremy Corbyn to sack the head of his election campaign.
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Prince Harry pictured in Afghanistan in 2012
Security Minister Ben Wallace told the Sun: “We know Corbyn and his commie friends hate Britain but more worrying is their constant acceptance of terrorism.
“They view our brave soldiers and police as the enemy.”
Meanwhile Tom Tugendhaut, who served in Afghanistan and is campaigning for re-election in the Tunbridge and Malling constituency, added: “Offering a British soldier as a hostage to our enemies is disgraceful.
“All those that served our country deserve the same respect.
The young royal examines the cockpit of an Apache helicopter while stationed in Camp Baston
“Andrew Murray has consistently tried to undermine the British Armed Forces and he has no place in a serious national party.”
Soldiers, airmen, marines and sailors proudly wore their medals and were joined by other organisations like the Women's Auxiliary Air Force.
The Not Forgotten Association provides entertainment, leisure and recreation for serving, wounded or sick servicemen and women and veterans with disabilities.