Management at a garden centre restaurant have stopped providing tap water for customers, claiming it might not be safe to drink, but they deny it is a move to force people to buy bottled water.

Roberta Law, of Harwell, has lunch in the restaurant at Notcutts Garden Centre, Nuneham Courtenay, about once a week. She always asks for a glass of tap water to accompany her meal.

Mrs Law, 64, said: "I was shocked when I was told that tap water was no longer available. They said it may not be safe to drink and that I should buy a bottle of water for £1. That's a lot of money for a pensioner to pay if they want a drink of water or who may need water to take a pill.

"Notcutts are forcing people to pay for water when it used to be free."

But Notcutts restaurant manager Jackie Lee denied it was a move to boost takings and said they had decided to withdraw the tap water because of worries about contamination. She added: "We don't have a separate drinking water tap and have to use water taken from the taps over our sink. We wash up in the sink and cleaning materials come into contact with the area.

"There's a risk of water drawn off for drinking purposes being contaminated and we don't want to run the risk of harming customers. We may look at installing a separate water tap."

The manager of South Oxfordshire District Council's environmental health food and safety department, Nigel Pinnock, said: "Following a complaint about the possibility of contaminated water we visited the restaurant. We're satisfied there's no problem with the quality of water supplied to the garden centre.

"The risk of contamination to water drawn off from taps over the sink is minimal but it is a matter for the garden centre if it doesn't want to take that risk and wants to charge for bottled water."