Parents have been warned that their children face a "dietary timebomb" in a new report into the drinking habits of the nations youth this week.

Some 21% of seven to ten-year-olds consume nearly ten cans of fizzy drinks a week, while only 12% of children choose to drink water, according to research released by the water producer Highland Spring.

The report said that children's thirst for sugary soft drinks was increasing and partly blames the lack of healthier alternatives in schools.

The report, entitled "A spoon full of sugar", reveals that some 94% of seven to ten-year-olds drink fizzy drinks and 50% of children don't drink at all at school.

In a statement Highland Spring said: "Access to palatable drinking water is a basic human right yet many children are forced into drinking from taps in school toilets - conditions no adult would tolerate in their workplace. Yet when school canteens are sponsored by fizzy drinks suppliers and water fountains don't exist, it's very difficult for children to make a healthy choice."

Aroud 80% of all fizzy drinks children consume are bought by their parents and yet more than 50% of four to 18-year-olds suffer from tooth erosion.

Professor Elizabeth Kay of Turner Dental School at Manchester University said: "The problem for children is that water has not been fashionable. Sweet, acidic drinks do huge damage to children's teeth but it's alarming to discover that it's parents who are buying the majority of them."