Peace campaigner Brian Haw, who has died of lung cancer, protesting outside the Houses of Parliament in 2007 (Reuters)
A joint statement on Haw's website from his family and supporters said: 'It is with deepest regret that I inform you that our father, Brian, passed away this morning.
'As you know he was battling lung cancer, and was having treatment in Germany. He left us in his sleep and in no pain, after a long, hard fight.'
Haw had been fighting for his right to continue his protest in Parliament Square, with authorities spending years attempting to evict him.
Haw's protest began on June 2, 2001, in response to British and American bombing raids on Iraq prior to the, and grew wider in scope following the invasions of Afghanistan and Iraq.
In 2005, the Serious Organised Crime and Police Act was passed, which restricted the right to protest in designated areas around the Houses of Parliament.
And in the latest efforts, the Greater London Authority managed to have Haw and his supporters removed from the grass area at the centre of the square. Later this year Westminster Council is set for a court bid to get the camp moved off the pavement, which could see it removed permanently.
In the statement on Haw's website, fellow members of the Parliament Square Peace Campaign said that he had been 'relentlessly persecuted' and that the authorities 'should forever be ashamed of their disgraceful behaviour towards Brian'.