A third of Kingston’s outstanding schools could see their top ratings threatened by new Ofsted rules to drive up standards.

The new Chief Inspector of Schools announced last week that, from September 2012, schools could not be judged outstanding unless teaching also received top marks.

Two of Kingston’s outstanding primary schools, Burlington Infants and Christ Church, Surbiton, received a "good" rating for teaching when last inspected.

Among outstanding secondary schools, teaching at Tolworth Girls’ and Coombe Girls’ was good, and excellent overall at Holy Cross and Richard Challoner, but only good in sixth form.

Because they received top grades overall, none of the schools have been fully inspected since at least 2009.

Ofsted head Sir Michael Wilshaw said: "We need clear and demanding criteria for a school to be judged ‘good’ or ‘outstanding’. A good school should have at least good teaching, and an outstanding school should have outstanding teaching."

An Ofsted spokesman said a wealth of information would decide which outstanding schools were reinspected, not just their previous inspection report.

Councillor Liz Green, executive member for education, said: "If you are an outstanding school, teaching should be outstanding because schools are first and foremost to teach.

"I would not like to see any of our outstanding schools be culled because their level of teaching was good. That’s unfair.

"They need to have an opportunity to bring their teaching from good to outstanding. I think it depends on how it ends up being implemented."