Plans to reduce the size of a scheme to turn a disused Twickenham hospital into a school have been criticised.

Richmond Council has struck a deal with South West London and St George’s Mental Health NHS Trust to buy a portion of St John’s Hospital, in Strafford Road, to increase the number of primary school places in the area.

Among the options are the expansion of the junior department of St Mary’s CE Primary School from two classes a year to three, moving it from Richmond Road to the hospital site and putting a one-form primary school in its place. Another is to put a new primary school on the St John’s Hospital site with one class per year in the infant department and two a year in the junior department, with St Mary’s unchanged.

Both plans involve putting an extra class at Orleans Infant School, in Hartington Road, and would have increased the number of classes per year in the area from five to seven. Both would have seen more than 300 children on the hospital site.

But, last week, Richmond Council’s new Conservative cabinet were updated on the scheme and plans now involve either a two-class per year junior school for St Mary’s or a one class per year primary school on the site.

The new proposal would see less than 250 pupils on the site and is a further change to primary school plans for the area. The previous Liberal Democrat administration had planned to turn both Orleans and St Stephen’s Junior School, in Winchester Road, into two-form primary schools but it was scrapped after governors at the junior school felt the budget was not sufficient.

Councillor Malcolm Eady, Richmond Liberal Democrats’ education and schools spokesman, said: “Parents have not been informed of the change and they have tried to conceal things in a technical report. There is also no explanation of how this fits into overall borough plans for primary school expansion.”

Coun Eady described the approach as “chaotic” and said his party’s plans took into account a lack of Government money – he added initial plans were the minimum required given the circumstances.

Councillor Paul Hodgins, Richmond Council’s cabinet member for schools, said: “These options are only one part of the jigsaw in seeking to provide sufficient places in the area and we will be consulting with schools and parents on other plans in the autumn.”