Hastings Hotels Group, which already owns six properties in Northern Ireland and one in Dublin, has purchased the former office block for £6.5m.
Planning permission for a hotel of "major city international quality" will be submitted within a few weeks. Belfast Architects WDR & RT Taggarts have been engaged to develop the designs.
The new hotel is expected to create 150 new jobs in the hospitality sector.
A statement by Hastings Hotels said: "Its prime city centre location is ideally situated to meet the urgent demand that the hotel sector requires to satisfy the growing business activity and the increase in tourism prospects."
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