A planning application to demolish the entire hospital was submitted to the borough council in May.
A spokesperson for the board said: “The option of retaining the Victorian frontage of the hospital unfortunately would have meant that the business care objectives and clinical requirements for the development of the new facilities would not be met.
“The proposed materials do include reclaimed bricks from the current building and we consider that the heritage impact of the scheme will be outweighed by the benefits to the public.”
Hinckley and Bosworth MP Dr Luke Evans supported the plans, adding the current building was “no longer fit for purpose”.
“To ignore the realities facing us and request a delay at such a late stage in the process, after the NHS has put time and money into creating these plans, risks our community losing this funding and access to vital local healthcare services altogether,” he said.
In response to Bray’s letter, the Department of Health said: “We are pleased to be providing more than £7m for a day case unit in Hinckley which will greatly benefit patients and the community.
“The funding is due to be spent this financial year with delivery scheduled by February 2026.
“Any requests for further funding or to change or delay the scope of the project, would have to be made through the appropriate channels for consideration.
A public consultation on the development ended on 13 June.