Google should be “held to account” over alleged unlawful collection of personal data, the leader of a campaign group launching a mass legal action against the tech giant has said.

Former Which? director Richard Lloyd claims Google unlawfully harvested information by bypassing privacy settings on Apple iPhone handsets.

The campaign group, headed by Mr Lloyd, reportedly hopes to land at least £1 billion in compensation for an estimated 5.4 million users of the device.

The claim centres around allegations that, between June 2011 and February 2012, Google placed cookies, small text files which give websites a way to track a user’s preferences and deliver personalised advertisements, in iPhones, to fool the devices into releasing data from Safari, Apple’s web browser.

Mr Lloyd said people should be able to get redress in a simple way.

He told Radio 4’s Today programme: “There is some precedent in the UK courts, where a small group of individuals settled privately with Google, but what has never happened, and what I think is a huge gap in the regulatory system, is everyone else who was affected by this workaround, the privacy settings on Safari, they’ve never had any access to redress at all and that’s what we’re trying to tackle with this claim.”

He added: “What we’re asking the court to do is allow me to represent the five and half million people that were affected, all on the same basis that their data rights were breached, and that Google should be held to account.

“At the moment there is a sense that Google and similar tech giants from Silicon Valley are behaving as if they are above the law, that they can’t be held to account in the courts in this country.”

iPhoneAn estimated 5.4m iPhone users could be in line for compensation (Lauren Hurley/PA)

A Google spokesman said: “This is not new – we have defended similar cases before. We don’t believe it has any merit and we will contest it.”

In August 2012 Google agreed to pay a civil penalty of 22.5 million US dollars (£15.1 million) to settle charges brought by the United States Federal Trade Commission, that it misrepresented to users of the Safari browser that it would not place tracking cookies or serve targeted advertisements to those users.

It is reported to be the first such mass legal claim of its kind in the UK.

Legal firm Mishcon de Reya has been appointed to represent the group – Google You Owe Us.

Partner James Oldnall, who is acting for Mr Lloyd in the legal action, said: “Whilst the total sums made by Google from misusing this data are likely to be large, the damages suffered by each individual are relatively small.

“A representative action such as this can be brought on behalf of all consumers and removes the need for individuals to bring an action, which they are unlikely to do.

“In this way Google and other tech companies can be held to account in relation to any alleged breaches of UK data protection law.”

He said data had become an “important new currency” and was valuable to large corporations, therefore consumers needed methods which could effectively police the rights given to them.

The case is reported to start next year.