NHS bosses want to build a temporary two-storey extension to the accident and emergency department at the Royal Sussex County Hospital in Brighton.

The modular building would be linked to the existing A&E department and would enable medics to treat more patients.

The building would be an “interim measure” and stay until completion of the £485 million modernisation of the Royal Sussex site although no date was given by hospital bosses.

University Hospitals Sussex NHS Foundation Trust, which runs the Royal Sussex, said: “The principal purpose of this facility is to supplement the facilities of the main A&E department, which requires additional capacity and has been severely overstretched by the current caseload of Covid 19 infections.

“The facilities will provide essential extra capacity, rationalise the access to urgent treatment and support the streaming of A&E patients in line with the NHS Five Year Forward View.

“The modular building is intended as an interim measure while more extensive redevelopment of the hospital is in hand and, once the current project is completed, the A&E department will relocate to its new accommodation.

“The lifespan of the building will be limited but the trust is not able, at this point, to predict how long it will be required.

“The proposed site for the building is the parking and manoeuvring space outside the existing A&E reception point.

“The proposed building is sited above the retaining wall which borders Bristol Gate and occupies a row of parking spaces between the existing single-storey A&E building and the main refuse storage compound for the hospital.

“It is proposed to reposition the refuse storage compound to optimise the use of the available space while maintaining the storage capacity.”

The hospital trust has applied for planning permission for the changes to Brighton and Hove City Council.

If granted, the extension would have a new waiting room, treatment rooms, accessible toilet and utility room on the ground floor.

The first floor would have offices, cleaners store, toilets and a “simulation room” for training.