The Government has recruited 15 manufacturers from Europe, Asia and North America to supply cheaper, greener cars over the next four years, The Times has learnt.

The cost will be shared by 38 government departments and agencies which have agreed to “green’’ their fleets in exchange for large discounts on cars available under the partnership.

The programme, which is limited to light commercial cars and vans and does not cover heavy diesel vehicles, aims to slash carbon emissions from the public sector fleet by 15 per cent by 2010-2011 under targets set by the Government this year. The programme is expected to save departments £100 million, and comprises some of the efficiency savings to be outlined in next week’s Pre-Budget Report.

The initiative, spearheaded by the Office of Government Commerce (OGC), comes as Britain faces pressure to fall into line with EU moves to limit greenhouse emissions, the debate over green taxes and national efforts to combat climate change.

After a tender process of unprecedented size and scale earlier this year, Vauxhall, Nissan, Toyota, Volkswagen, Honda, Ford — including Volvo — and BMW won places in the programme.

Ford, which already supplies Jaguar and Volvo cars as well as its “Blue Oval” models to Whitehall and the NHS, will now have access to a vast range of agencies and suppliers.

Ford currently supplies Jaguars at close to half price to the Government Car and Dispatch Agency, which organises cars for Ministers.

The NHS, which keeps a fleet of 48,000 cars, and the Department for Work and Pensions, which has 2,500 vehicles, joined the programme to satisfy targets set by the Government. The NHS expects to spend £420 million replacing its fleet with the new range of cars, £19.7 million less than it would have cost the department to replace its fleet with the same vehicles again.

Departments wanting to join the programme must calculate the amount of pollution caused by their current fleet by entering engine size, carbon dioxide emission and “Euro 4’’ engine rating into a model designed by the OGC. They can then access a database of cars available under the programme, and “shop” for their desired vehicles. They are expected to use the OGC model to monitor the desired fleet’s carbon footprint.

Annual reports outline the department’s progress on environmental targets.

Lord Hunt of Kings Heath, the Work and Pensions Minister, pledged to use the scheme to meet the Government’s targets. “This will not only contribute to the Government’s efficiency goals but will also help the public sector to hit its targets on vehicle emissions.”

The Department for Work and Pensions expects to save about 15 per cent with the discounts that are available under the scheme.

Toyota, which currently supplies the popular Prius model being adopted by ministers, hopes that the programme will entice departments to its British-made Avensis model