Primary school teachers could see maximum class sizes increase to 32 pupils if recommendations from a London council are adopted by the government.
The chief executive of Sutton council Niall Bolger has urged the education secretary Michael Gove to increase the maximum class size limit to help authorities save money.
Mr Bolger believes that upping the maximum number of children a school can have in one class would not damage pupils learning but would help councils accommodate rising numbers without increasing their spending.
He said that his council have spent some £7 million creating extra places for pupils which would not have been necessary were class sizes allowed to be bigger.
The current limit on infant class sizes is set at 30 pupils and was introduced by Labour in 1998 after they made it a key pledge in their election manifesto in 1997.
Councils across London have received a letter from Mr Bolger asking them to support his recommendation.
Mr Bolger argues that the limits on class size were introduced at a time when school places were in a surplus and the population level was lower.
He said: "We do not wish to eliminate all parameters for class sizes but we consider 32 to be a pragmatic compromise between educational viability and financial prudency."
However, Councillor Peter Walker who is Merton council's cabinet member for education, claimed that Mr Bolger's suggestion was myopic.
"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," he said.
Meanwhile, a spokesperson from the Department for Education acknowledged that the rising birth rate was causing problems in some area but said that the law was clear that the limit for infant class sizes is 30 pupils and investment was being targeted to relieve the pressure on the worst-affected areas.
"No parent would want their child taught in a huge class," they said.
Posted by Harriet McGowan