Dame Vera Lynn and Nicholas Soames MP are backing the Argus campaign to keep accident and emergency services in Haywards Heath.
Proposals to downgrade the casualty department at the Princess Royal Hospital were branded "crazy" by Dame Vera.
Civic leaders and GPs serving people in Mid Sussex are concerned at proposals being considered by health chiefs for the Princess Royal's A&E facilities.
The plan could mean patients who need emergency surgery having to go to hospitals in Brighton, Redhill or elsewhere instead of Haywards Heath.
Critics say that could cost lives as seriously injured people are transferred by ambulance on congested roads.
Health chiefs argue that most patients would still be treated at the Princess Royal, including asthma and heart attack victims.
They say those transferred to other hospitals would get the best possible specialist care.
But Dame Vera, president of the Princess Royal's League of Friends, said: "I am all for the Argus campaign. I don't fancy these changes at all.
"If people are seriously injured, the quicker they are attended to the better and the more chance they have of survival."
Dame Vera, who lives in Ditchling, added: "Going into Brighton, you are at the mercy of the traffic. It seems crazy to me."
Mr Soames, MP for Mid Sussex, who has a cottage just outside Handcross, said: "The Princess Royal Hospital, serving a large and still growing population, must have the proper facilities needed to cope reasonably with serious accidents.
"We must of course have a proper A&E service."
What do you think? Please write to Save Our A&E, Evening Argus, 5 Church Road, Burgess Hill, RH15 9BB.
Alternatively, send an e-mail to matthew.james@argus-btn.co.uk with a copy to phil.dennett@argus-btn.co.uk
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