The GMB union says it expects between five and ten thousand people to join a march through west London today in protest against the closure of emergency departments at several hospitals.
Plans have been outlined for the closure of facilities at Charing Cross and Hammersmith & Fulham Hospitals, and Ealing and Central Middlesex Hospitals.
The Union says the closures would lead to longer waiting times at other hospitals.
A spokesperson for NHS North west London said the plan was currently being consulted upon, and they would like to hear people's views.
The march will start in Shepherd's Bush at midday.
More top news
Goals from Charlie Austin, Dusan Tadic and James Ward-Prowse consigned Slaven Bilic's men to their fourth straight Premier League loss.
A bizarre protest against BP sponsorship at the British Museum used theatre, sea shanties and 'mermaids' to 'summon a Kraken'.
Two men have been jailed for robbing a man aged 79 as he was washing his car.