A Reading bus firm is to stop using a petrol substitute to run its vehicles because of spiralling costs.
Reading Borough Council and Reading Buses have said they can no longer use bio-ethanol fuel, blaming the current economic climate.
Fourteen buses on the town's busiest route have been using the alternative fuel for more than a year.
The buses will now be converted to run on bio-diesel, which the council says will halve running costs.
The council said, at current prices, the bio-ethanol buses cost £590,000 a year, compared with £236,000 on bio-diesel.
Reading Borough Council and the board of Reading Transport, which is owned by the council, has also ordered an inquiry after it emerged the buses had been running on bio-fuel made from paper bi-products instead of sugar waste, as originally agreed.