The changes affect the company's range of Go Anywhere day tickets, Bridlington day rover tickets and Bridlington weekly tickets, and the Hull and Hull Plus day rovers and weekly tickets.

EYMS chief executive, Peter Shipp, said the price rises had been delayed for as long as possible in the hope that the fuel price might start to drop back, but instead the cost of fuel has continued to rise and has only this week reached a record high

"We were hoping not to increase these fares just yet,"said Mr Shipp, "but the situation has been forced on us. Revenue from these particular tickets is only a small part of our total income so, although we will avoid it for as long as possible, I cannot rule out more general increases in our fares in the fairly near future."

To help promote the fact that the weekly tickets are now available through the PayPoint network, the prices of the Hull Plus (£7.50) and the Bridlington (£7) weekly tickets will not be raised until the end of March for passengers buying them through PayPoint outlets.

"If the government goes ahead with its planned 2p per litre rise on fuel duty from April, and if it does not offset this by increasing the grant we get for fuel used on local bus services, then a general rise in fares will become almost inevitable, and I cannot rule out the possibility of some service reductions as well," continued Mr Shipp.

"Meanwhile, the Department for Transport is doing its utmost to cut the payment we will get from April for the new national concessionary fares scheme, and it could well be that bus operators will end up worse off than they are now as a result, despite having to carry more free passengers.

"It is pretty clear that the government got its sums totally wrong when the then Chancellor Gordon Brown announced this national scheme in his Budget speech last year.

"The money allocated to the scheme for England is woefully inadequate and there are signs of panic measures in the department to try and reduce the reimbursement to operators. Apart from being completely unfair, this could have disastrous consequences for the bus network, especially in rural areas, because quite simply we may well end up carrying more people for less money."