A health council fears the location of a proposed new breast cancer unit could be decided by which site receives planning permission first.

Health chiefs were expected to make a decision last week on whether to proceed with a proposal to transfer the Nigel Porter Unit for Breast Care out of the Royal Sussex County Hospital in Brighton to the Princess Royal Hospital in Haywards Heath.

The unit needs to expand to cater for increased demand and to meet government targets.

But health chiefs delayed making a decision last Thursday and said applications for outline planning permission would be made to Mid Sussex District Council and Brighton and Hove City Council for a new unit at both locations.

That would give an indication of how quickly a unit could be built and what obstacles they could face.

Mid Downs Community Health Council (CHC), which represents patients in Haywards Heath, was disappointed a decision was not reached. A statement released by the organisation said: "The impression given was the option which could be most rapidly implemented would be the preferred option."

Residents in Brighton and Hove want the unit to be expanded into Rosaz House in Bristol Gate, Brighton, which is part of the Royal Sussex, opposite the oncology centre.

They are opposed to the transfer to Haywards Heath because of the transport difficulties and the fact the move means all the services associated with treatment would become divided between both sites.

The campaigners, together with retired consultant surgeon Nigel Porter and Dr Richard Sullivan, head of clinical programmes at Cancer Research UK, believe this is a backward step in cancer treatment.

Mid Downs CHC chief officer Carolyn Nurse said: "It is regrettable it is still not known whether the primary care trusts would be willing to fund the unit."

A final decision on a site for the unit is likely to be made in six months.