Soldiers, ex-soldiers and military families are set to speak out against the war in Afghanistan before joining a protest tomorrow.
Stop The War Coalition said today that Joe Glenton will become the first serving member of the military to attend an anti-war demonstration since the 2001 invasion of Afghanistan.
Lance Corporal Glenton, who is fighting a court martial for refusing to return to Afghanistan, will lead marchers from Hyde Park to Trafalgar Square, in central London, where a rally will be held as part of the campaign to bring British troops home.
Lindsey German, convener of the Stop the War Coalition, said today: "This will be the first time a serving soldier has openly attended a national anti-war demonstration.
"This shows how deep feeling against the war in Afghanistan goes. Barack Obama and Gordon Brown will soon find that this war turns out to be their Vietnam if they keep pouring in troops."
Joan Humphries, whose grandson Kevin Elliott, 24, from Black Watch, was killed while on foot patrol in the southern Afghan province of Helmand on August 31, will also join the demonstration.
She said: "I have supported CND all my life and have been involved in Stop the War since the march in 2003 when more than a million people were on the streets.
"Kevin knew my feelings, but there were no jobs, education was poor and the politicians were dishonest and there was simply nothing else he felt he could do but join the army."
Peter Brierley will attend the demonstration in memory of his son, Lance Corporal Shaun Brierley, who was killed while on duty in the Gulf.
Mr Brierley, from Batley in West Yorkshire, refused to shake the hand of Tony Blair at a memorial at St Paul's Cathedral for soldiers who died in Iraq. He told the former prime minister, "You have my son's blood on your hands."