Customers of internet service provider (ISP) V21 have been left with no internet connection since Wednesday because of a dispute over payments with its wholesale provider, Netservices.

The legal wrangle, is affecting around 9,500 end users of V21, which was bought last month by another ISP Biscit and renamed V21/Biscit CSP.

Netservices, which provided broadband connections for V21 to sell on to its customers, said the dispute over payments with V21 had begun before Biscit's acquisition of the ISP.

"Our decision to terminate the agreement with V21 was taken due to V21's repeated failure to pay charges due under the contract," Netservices said in a statement on its website.

It said it even after the acquisition by Biscit, it had "sought to identify and acceptable basis under which the supply of services to V21 might be maintained but without success".

Netservices has suggested V21 customers migrate to Ezeedsl, an ISP run by network provider, 186k.

However, this has prompted V21/Biscit to issue legal proceedings against Netservices. Yesterday a V21 press release said the ISP "will begin legal proceedings against Netservices seeking substantial seven-figure damages. The legal action results from Netservices' decision to novate some of V21's customers to another service provider".

This charge has been refuted by Netservices which said: "We have attempted to help end-user customers by enabling them to contact an alternative service provider which is Ezeedsl should they wish to do so."

However, the choice for V21 customers is stark. Although Biscit has told affected V21 customers to demand their migration authorisation code (MAC) from Netservices so they "can log on to www.v21.co.uk/migration to be reconnected to its superfast broadband services and receive one month's free broadband compensation", this is unlikely to happen.

Netservices said it can't provide these codes to customers because it would contravene "its wholesale distribution agreement and be a breach of its customer (ISP and resellers) confidentiality".

This means V21 customers are faced with either migrating to Ezeedsl, which costs more than their original service, if they want to get back online quickly, or waiting until around 24 November 2006 when the service will be terminated. Their lines will then be untagged, allowing them to pick an alternative ISP.

However, this could leave these people with no broadband connection until well into December.

In the meantime, V21 has offered a temporary solution for its customers. It said: "Our parent company has made a dial-up service available to you so that you can continue to send and receive emails and connect to the internet."

The dial-up number is 0845 604 1190, user name is 'v21local', and the password is 'dialup'.