Once the tendering process starts, it is expected that selection of the partners could take up to 12 months.
Charmer said: "We think it should be delayed further. Some components are incomplete. But ministers are pushing for it." It is understood that the government is concerned that the scheme will fall too far behind if it is not advertised before departmental preparations begin for the general election, widely expected to be held in early May.
A Procure 21 spokesperson denied that the scheme would be advertised that quickly, but confirmed that NHS Estates wanted to get an OJ notice as soon as possible.
The Major Contractors' Group warned earlier this month that the election would lead to further delays. NHS Estates had initially promised that projects would be launched early this year.