BT Openworld has joined forces with CyberPatrol to offer content filtering software.

The service is aimed at helping parents protect their children when they are online.

It will block websites which parents feel may be unsuitable for children and enable them to filter inbound and outbound chat room content or block it completely.

The service can also block children from disclosing personal information such as phone numbers and addresses.

Parents who do not want their offspring online for hours at a time will be able to use the service to allocate the amount of time spent online by individual family members.

There is no limit to the number of user profiles that can be set up and customers can tailor their service depending on what they think is suitable for their family.

All BT Openworld customers can download the software via its Safer Surfing website, and try the software free for 45 days. After this the cost is £31.95 for a year's subscription.

Duncan Ingram, BT Openworld's senior vice president, said BT chose CyberPatrol over other parental control software because of its flexibility. He also said that BT was investigating ways of introducing payments for people who want to spread the cost over the year.