Sutton Council is urging the Government to increase primary school class sizes.

Niall Bolger, Sutton Council's chief executive, has written to every London borough in order to garner support for the plans.

Sutton Council want to increase primary school class sizes from 30 to 32 following analysis into the cost of providing extra school places.

In 1998, new legislation was brought in to limit the infant class sizes to 30, but Sutton Council believe the number is not financially viable.

The letter, sent to the chief executive of every London council this week, states: "The purpose of this letter is to request central Government to consider raising the ceiling of infant class sizes to 32 pupils per class in order to enable councils to meet their statutory obligations to educate all their young citizens within their financial envelope."

Mr Bolger wrote: "We do not wish to eliminate all parameters for class size, but we consider 32 to be a pragmatic compromise between educational viability and financial prudency."

Critics believe the figure of 32 could set a precedent for even larger increases.

Councillor Peter Walker, Merton’s cabinet member for education said: "I strongly urge those with responsibility for education in London to oppose this regrettable initiative. Increasing class sizes in our schools at this time is short sighted, will threaten school standards, is unfair to our children and will endanger our economic prospects. "

In a statement, Niall Bolger, Sutton Council’s chief executive, said: “Increasing class sizes is not a Sutton Council policy or something that has been discussed at a political level. My letter is a basic piece of research so that senior officers can present councillors with well informed choices. “There is a dreadful shortage of primary school places and we can’t ignore the situation, especially when our schools, which are some of the best in the country, are attracting so many families.”

Sutton Council has spent £7m funding additional classes for September 2012. It has been expanding primary schools for a number of years and all easy options to meet demand have been exhausted.