Bottled water has been banned from Parliament meetings in a victory for the Evening Standard's Water On Tap campaign.

The authorities who run the Commons have announced they will serve nothing but plain tap water in future.

The move will save taxpayers the cost of around 16,200 one litre bottles that are supplied free of charge to MPs and their staff during committee meetings.

Canteens in the House are already fitted with filtered mains water dispensers for use at meal times, although more than 100,000 litres of bottled water are sold in its bars and restaurants each year.

In a statement, the Commons facilities department said: "We are working with colleagues in the House of Lords to replace bottled water with tap for committee meetings. We expect to be able to do this within the timescale the Government has set for its departments and agencies." The move comes a day after Chancellor Alistair Darling chose plain tap water as his Budget tipple in a gesture of support for our campaign.

The Standard is calling on London restaurants to offer diners free tap water, along with the option of buying still or fizzy from bottles, to remove the stigma of having to ask for it. Last week, Cabinet-Secretary Gus O'Donnell announced that only tap water will be served at Whitehall meetings in future.

Gordon Brown's Cabinet sessions every Tuesday will follow suit.

The Department for Environment, Food and Rural Affairs, the Food Standards Agency and the Department of Business, Enterprise and Regulatory Reform have already made the switch to tap water at meetings.

It is kinder to the environment because it is responsible for about 300 times fewer carbon emissions than producing and transporting bottles.

It does not create waste packaging or have to be taken long distances by road, sea or air.

• Islington council is encouraging its workers to drink tap water.

It has banned the sale of bottled water in staff canteens and shops and will not provide it in meetings, saving more than £8,000 a year.

Council leader James Kempton said: "What sense does it make to have water shipped around the world in bottles when we can just turn on the tap?

"Everyone ought to be reducing the amount of waste they produce and thinking about the environmental impact of their consumption."