It now intends to add to the site by acquiring the adjoining Grade I listed building, formerly the Bristol Branch of the Bank of England.
The building was built in two parts in 1843 and 1868 with two road frontages to Broad Street and to Small Street.
Trevor Osborne, of the Bath-based property group, told the Bristol Post the proposal was still at "pre-application" stage.
"Including the former Bank of England building means we can get an increase in the number of bedrooms. It will be at the five-star at which we were aiming but we wanted nearer 100 rooms," he said.
If the council gives the green light, the extended hotel will feature around 90 bedrooms, substantial public areas, dining rooms, bars, function rooms, a large spa and a rooftop swimming pool.
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