As NATO leaders were discussing ending the war in Afghanistan in Portugal, thousands of people protested in London over the conflict.
Military families led the bulk of the demonstrations followed by a sea of anti-war placards and banners against cuts to government spending.
Protesters chanted "When they say warfare, we say welfare" as they moved through the streets of central London before finishing at Trafalgar square for a series of speeches.
The demonstration took place as the Prime Minister attended a Nato summit in Lisbon, where an agreement was reached which will see Afghan forces take over full responsibility for the country's security in 2014.
David Cameron said the Coalition Government had set a "firm deadline" of withdrawing British troops from a combat role by 2015.