MetroCard rates will go up by 8 per cent on July 20, with companies blaming rising oil prices.

But John Sykes, who represents the Calderdale public on the West Yorkshire Passenger Transport Authority Passenger Consultative Committee, said: "The bus operators are jumping the gun a bit, in that they buy their fuel in advance.

"The fuel at the moment does not really affect them. They are quite happy with the price they are having to pay.

"People are also turning from their cars to buses and trains, and so the increased revenue from more people using the services should cancel out any increases in oil prices."

Firstbus, Calderdale's biggest operator, has refused to rule out individual fare increases.

A company spokesman said: "The worldwide oil market is currently very volatile and we are monitoring the situation as we try and absorb these rising costs. We cannot rule out having to raise bus fares in the future."

Arriva Yorkshire will be putting up individual fares, as well as increases to MetroCards, but will not be releasing details until the end of the week.

Howard Maude, a former passenger representative on the PCC, said: "They have a legitimate excuse on this occasion – oil prices are having an effect on them.

"But they have got to realise that they can't expect to make the same amount of profit in this situation.

"When the oil gets back to something resembling how it was, they won't be reducing prices. Deregulation has not worked.

"You can't put services and profit together – it does not add up," he said.

A spokesman for Halifax Joint Committee said: "We have no plans to raise fares in July, but it is an ongoing process and we tend to look at fares quite regularly to see if there is anything we can change, rather than set blanket increases."

Neil Walsh, managing director of TJ Walsh, previously said the bus company was looking at increasing fares but was trying to hold back.