Local councils are to be given a legal duty to close gaps in achievement between the most disadvantaged children and their better-off classmates.
Speaking at a fringe meeting, Beverley Hughes, children and families minister, said the Childcare bill, due before Parliament in November, would require local authorities to improve the lives of all under-fives in terms of achievement, health, safety, enjoyment and economic well-being.
"I think that is a really radical duty to propose in law a responsibility to tackle inequality," said Ms Hughes.
The minister said her Bill would also mean local authorities would have to ensure there was sufficient childcare in their areas for all parents who wanted to work.
Ofsted and Audit Commission inspections will monitor how council perform their new duties.
Ms Hughes told another fringe meeting that she felt that teachers were working hard but "they are not focusing enough on those who need the services the most". "It's not enough just to get people up to a certain level, we need to reduce inequality as well," she said.