Strong winds mean firefighters are struggling to bring the fire at the Royal Albion hotel under control.
The fire is still raging some six hours after it was first reported.
The historic hotel in Brighton’s Old Steine is causing smoke to cover the city with hundreds of emergency personnel expected to stay on scene overnight.
Nearby residents have been evacuated from their homes and placed in emergency accommodation.
There have been no reported injuries.
A spokeswoman for East Sussex Fire and Rescue Service said: “High winds are creating difficult conditions for fire crews and firefighters are expected to continue dealing with the fire through the night.
READ MORE: Brighton's Royal Albion hotel is on fire
“As a precaution East Sussex Fire and Rescue Service working alongside Sussex Police have evacuated surrounding buildings.
“We are aware of significant smoke in the area which is being made worse by wind. We strongly advise you to avoid the area.
“There are no reports of casualties at this time.”
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