A protest will be held this afternoon when a council watchdog meets to discuss controversial changes to hospital services.
Campaigners are calling on the Calderdale and Kirklees Joint Health Scrutiny Committee to halt a consultation over proposals to centralise A&E care in Halifax.
Huddersfield Royal Infirmary will lose its A&E if the plan goes ahead and the town’s main hospital could be knocked down.
Calderdale Royal Hospital would become a central A&E centre under the proposals, designed to tackle a £280m funding gap.
Protesters will gather at Halifax Town Hall from 3pm today ahead of a meeting of the scrutiny committee, which could refer the proposals to health secretary Jeremy Hunt.
Fears have been raised that the changes are financially-driven and that longer ambulance journeys to hospital could compromise patient safety.
Details of the planned shake-up are set out in a consultation document release by Calderdale and Greater Huddersfield Clinical Commissioning Groups (CCGs), which control the local NHS budget.
NHS action groups in Halifax and Huddersfield claim the proposals would not meet the health needs of the population.
Paul Cooney, secretary of secretary of Huddersfield Keep Our NHS Public, said: “Our health needs are for evidence-based, comprehensive, universal, equitable and value-for-money health care.
“The health care proposed in the consultation document is none of these things, as far as we can see. And we’ve looked hard.”
The groups also claim that the consultation is meaningless because it is only asking the public for their views on a single option for the future of hospital services.
NHS campaigners said the scrutiny committee could immediately halt the hospital shake-up if it decides the consultation process is flawed.
Jane Rendle, who chairs the Calderdale 38 Degree NHS Campaign, said: “The hospital re-configuration would compromise the quality of care, but the consultation document doesn’t mention this.
“And the proposal is made for financial reasons, not to improve the quality of care.”
The proposals could leave the whole of Kirklees with no full A&E department after Mid Yorkshire Hospitals Trust decided to downgrade Dewsbury’s emergency department to an “urgent care centre”.
Mid Yorkshire’s plan was referred to the secretary of state in 2013, but Jeremy Hunt ruled that it could go ahead.
Christine Hyde, chairwoman of North Kirkless Support the NHS, said: “We’ve now had time to see that the Wakefield and North Kirklees single option that was consulted on should not have gone ahead.
“Pinderfields now suffers from delayed ambulance handovers and overcrowding, while patient care at Dewsbury has suffered as the district hospital is being downgraded to a planned care clinic and urgent care centre.”