Trade union activists say their annual May Day march will commemorate two of the titans of their movement; the former leader of the RMT Bob Crow and the former Labour MP Tony Benn.
The London May Day Organising Committee said it wanted to pay tribute to their work but also put across the message that the movement should not just mourn but also organise to fight for rights for workers.
More top news
British police have closed some traffic outside the road leading to 10 Downing Street.
Metropolitan Police officer, Tom Harrison, has been crawling the course since the race began on Sunday morning.
The Old Bailey heard how Syed tried to get weapons online, including a bomb vest, and trawled the web to find a busy area launch an attack.