Sir Martin Sorrell, the chief executive of WPP, has said businesses continue to underestimate the importance the Edward Snowden's NSA electronic surveillance revelations have had on consumer attitudes to privacy and security.

Sorrell, speaking at the Ad Week Europe conference in London on Monday, said the global advertising and marketing industry had failed to grasp the importance of the ramifications of the revelations to their clients.

"People understate the importance of Snowden and NSA," he said. "[They] underestimate the impact on consumers, and if you take the hacking going on – credit card information, etc – there are two things [going on]. One is privacy and the other is security or secrecy. If you solve the security thing – a hacker-proof system, which may be an oxymoron – if you can solve the safety issue, the privacy issue falls away."

Sorrell made the comments while in conversation with Robert Thomson, the chief executive of Wall Street Journal and Times publisher News Corp, who said that the company has been examining its advertising proposition to tighten security and privacy.

"The NSA controversy has heightened awareness of [privacy and security]," he said. "Being very transparent with clients, readers, customers about the [browsing] experience they are having and consequences of it.

"We have been removing third-party networks for our sites, those ads are also data-gathering mechanisms. We want to be more respectful of privacy and also want to monetise our audiences our way. Being more focused on privacy is not bad for business, it can be good."

Sorrell highlighted the importance of the privacy and security issue to global marketing by citing WPP as an example: one-quarter of Sorrell's business, $5bn a year, comes from data and research services.

"We underestimate the importance of this, it worries me," he said. "Having access to data … is critically important. My point is that it is very important – people are underestimating its significance among consumers."

• To contact the MediaGuardian news desk email editor@mediaguardian.com or phone 020 3353 3857. For all other inquiries please call the main Guardian switchboard on 020 3353 2000. If you are writing a comment for publication, please mark clearly "for publication".

• To get the latest media news to your desktop or mobile, follow MediaGuardian on Twitter and Facebook