Millions of mobile phone users are inadvertently passing up their rights to privacy by upgrading to the latest handsets, campaigners have warned.

With their plethora of modern applications, the latest models disclose the user's location with a few yards, their internet shopping habits, friends and interests.

While phone providers are not supposed to pass on such data without permission, many people give consent for the information to be sold to marketing companies by not reading the terms and conditions of their contracts, it is claimed.

Human right campaigners have warned that such details give companies an unprecedented insight into people's lives.

Concerns have also been raised that this could lead to further invasion of privacy, should governments begin demanding access to the data in the future.

It was disclosed last week that Facebook, Bebo, MySpace and other social networking websites could be monitored by the government in an attempt to tackle internet crime and terrorism.