Shadow schools secretary Michael Gove hit back at claims this week that the Conservatives' central policy for school reform would not work.
Earlier in the week, Schools Secretary Ed Balls claimed the Conservatives' proposal to introduce a free school system, based on Swedish and US models, would hit school standards and be socially divisive.
Mr Balls' comments follow a statement on Monday from Per Thulberg of Sweden's National Agency for Education - the Swedish equivalent of Ofsted - who said any improvement in results was to do with pupils' backgrounds and not the new free school system.
Mr Thulberg told BBC's Newsnight: "This competition between schools that was one of the reasons for introducing the new schools, has not led to better results."
He added: "The students in the new schools, they have in general better standards, but it has to do with their parents, their backgrounds. They come from well-educated families."
Mr Balls said the comments built on additional evidence taken from the recent Trends in International Mathematics and Science Study that showed Sweden's average maths and science scores slump in international league tables.
But Mr Gove responded by contradicting the Swede's claims, stating that "academic evidence" has shown the free schools system has "raised standards for all". He added that President Obama "strongly supports" the model.
He said: "In Britain, richer people can go private or move house while poorer people often cannot escape bad schools.
"We will create a new generation of independent state schools funded by taxpayers but run by teachers and responsible to parents so that all parents get what they want - smaller schools with smaller classes, good behaviour, great teachers and restored confidence in the curriculum."