BTopenworld today announced yet more restrictions to its narrowband unlimited internet access products, Anytime and Surftime.

From 1 November BT's Anytime customers will be limited to 150 hours of flat-rate access per month, while Surftime users will be confined to 120 hours at evenings and weekends. Customers will be able to carry over up to 50 hours of unused credit per month.

But when BT launched its Anytime package, users paid a monthly fixed sum to surf the web for as long or as often as they wanted. This was then limited to a maximum usage rule of 12 hours in every 24.

"BTopenworld has in the past made it clear that extensive use by a small number of customers has an adverse effect on the quality of service enjoyed by the majority. We have taken action to limit this by asking customers to modify their surfing habits and, in some cases, removed the service," said the company's press statement.

BT categorically denied this was a way of pushing users towards its broadband services insisting it was "trying to improve the service for all users".

"Our research showed that most of our users are online for less than 50 hours a month, so it won't even affect the majority of users anyway," said a company spokesman.

BT will be emailing all its customers from today to notify them of the changes.