The former General Lying-In Hospital in York Road is to become a Premier Inn hotel after the NHS sold the building last year for £11 million.
Whitbread this week announced six new Premier Inn hotels in London, with 1200 rooms, to be opened over the next three years.
Just over a year ago we reported that Guy's and St Thomas' NHS Foundation Trust intended to sell the grade II listed building.
Land Registry documents show that the site – which includes the derelict former nurses' accommodation next door – changed hands last October for £11 million.
The owner is now a Jersey-registered firm called GLI (York Road) Ltd which has leased it to Premier Inn.
The building was refurbished five years ago at a cost of more than £4 million including a grant from the Guy's and St Thomas' Charity.
"We have exciting expansion plans for Premier Inn in London and today's addition of 1200 rooms is a great start," says Whitbread's chief executive Alan Parker.
"The capital is an important focus for Premier Inn, and there is an increasing need for high quality, affordable accommodation. Our further pipeline will position us as the largest hotel chain in London with at least 8,500 rooms before the Olympics in 2012."
The General Lying-In Hospital adjoins the Park Plaza County Hall which opened in February. The Park Plaza Westminster Bridge is under construction in the centre of the Westminster Bridge road junction.
The former hospital building opposite County Hall is currently used by Guy's and St Thomas' NHS Foundation Tust as a training facility and offices.
The hospital operated from the York Road building between 1828 and 1971 (apart from a wartime evacuation to St Albans, Herfordshire).
At least 150,000 babies were born at the hospital and it is said that Florence Nightingale took a personal interest in the associated midwifery training school.
The building became derelict and in later years it appeared on English Heritage's Buildings at Risk register. It was restored and refurbished for office use in 2003.
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