The Tories are hoping the furore over plans to fluoridate the water supply in South Hampshire will convince voters to back them at the next general election.

Julian Lewis, Conservative MP for New Forest East, named fluoridation as a key local issue that he believed would attract people to the Tories, following a pledge by shadow health minister Mike Penning that a Conservative government would review the way consultations are carried out to ensure such processes were not "enforced against the will of a population".

Dr Lewis, who said he had been "battling with Government" over the controversial public health measure for some time, said: "People do not wish to have this imposed on them, and under the Conservatives if people don't say yes it won't happen."

Prime Minister Gordon Brown has repeated the Government's support for the principle of fluoridation - but suggested it was a matter for health trusts and residents to determine locally.