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.
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Mayor of London Sadiq Khan is backing the scheme.
A spokesperson said the lightning strikes had left the "aircraft fuelling system unavailable."
Nearly 1,000 properties have been left without power, and road users have been warned of potentially hazardous conditions.