The Government will put £42 million behind plans to add fluoride to water, Health Secretary Alan Johnson has announced.
The cash works out at an extra £14m a year over three years to support authorities wanting to add fluoride to tap water.
Mr Johnson is urging strategic health authorities to consult with local people but believes fluoridation is an “effective and relatively easy way” to help poorer children by preventing dental problems in later life.
At present about six million people in England, mainly in the North East and West Midlands, receive water containing fluoride.
Children in non-fluoridated Manchester are twice as likely to have tooth decay as youngsters in Birmingham, where fluoride has been added for over 40 years, according to the Department of Health.
A York University study in 2000 found water fluoridation increased the number of children without tooth decay by 15%.
But critics argue that fluoride can cause fluorosis, where teeth become stained and pitted, and has even been linked to bone cancer. They also say there are other ways of increasing fluoride levels for children without forcing everybody to up their intake.
Mr Johnson said: “Fluoridation is scientifically supported, it is legal, and it is our policy, but only two or three areas currently have it and we need to go much further in areas where dental health needs to be improved. But there are people who hold strong views on this subject, so it is important that any proposed schemes are fully and widely consulted on.”
The British Medical Association’s head of science and ethics, Dr Vivienne Nathanson, said: “This is very good news. The BMA has been in favour of the fluoridation of mains water supplies for many years.”
Liberal Democrat health spokesman Norman Lamb said: “There is a case for fluoride to be added to water, but it is not up to the Government to impose this on the entire country from Whitehall. Local communities must have the power to decide if and when they want fluoride in their water supplies.”