NHS MANAGERS hope to advertise the revamped Paddington Health Campus to contractors next spring.
Project board member Julian Nettel said: 'We are taking our own independent soundings from a number of large consortia who have closely tracked the project.'
Mr Nettel said he had a 'pretty good idea' of who would bid for the scheme.
The latest masterplan developed by architect Sir Terry Farrell will use land owned by developer Chelsfield.
The firm looks increasingly likely to be bought out by a joint venture including Wembley builder Multiplex, but Mr Nettel said this would not affect the Paddington deal.
He added: 'Discussions are going very well and we anticipate them coming to a conclusion very soon.'
The centrepiece of the new development will be a 122 m tower housing St Mary's Hospital.Mr Nettel said this could mean some design work is carried out inhouse.
He added: 'It is not clear how much detailed planning we would need to do prior to working with a preferred bidder.'
Sir Terry's plans envisage the PHC straddling Paddington Basin around a public plaza.Mr Nettel explained: 'This is not another citadel which is closed to the outside world.
'This will give a completely different feel to any traditional approach to major hospital buildings, something which Westminster City Council have very much welcomed.'