The search industry needs to develop better global privacy principles for the collection, use and protection of data, according to web giants Microsoft and Ask.com. 

Both companies have pledged to work with other technology leaders, consumer advocacy organisations and academics to develop these principles, which could include sharing best practices to provide more control for consumers.

The move follows Google's recent announcement that it will delete cookies after two years of inactivity. 

"As search and other online services progress it is important for our customers to be able to trust that their information is being used appropriately and in a way that provides value to them," said Peter Cullen, chief privacy strategist at Microsoft.

"We hope that others in the industry will join us in developing and supporting principles that address these important issues. People should be able to search and surf without having to navigate a complicated patchwork of privacy policies."

Microsoft and Ask.com have proposed a meeting of leading search providers, online advertising companies and privacy advocates to discuss the implications of the proliferation of online advertising and search.

The aim is to create a set of privacy principles that take into account the requirements of all parties involved.

"Anonymous user data can be very useful to enhance search products for all users, but people should have access to privacy controls based on their level of comfort around the storage of their search data," said Doug Leeds, vice president of product management at Ask.com.

"We are committed to developing new ways to give consumers the control they are entitled to when it comes to searching online, and hope that others will join us in engaging in dialogue on these important issues."

To back up its call, Microsoft has announced an enhanced set of privacy principles for its Live Search and online advertising data collection, use and protection.

The company has outlined new steps including making search query data anonymous after 18 months by permanently removing cookie IDs, the entire IP address and other identifiers from search terms.

Microsoft will also implement new privacy features such as giving customers the ability to opt out of behavioural ad targeting by its network-advertising service.

The software giant has also said that it will join the Network Advertising Initiative (NAI) later this year when it begins to offer broad third-party ad serving. 

The NAI is a cooperative of online marketing and advertising companies created to address privacy and consumer protection issues in emerging media.