Facebook owner Meta has agreed to pay $US725 million (about $1 billion) to resolve a class action lawsuit that accused the social media giant of allowing third parties, including Cambridge Analytica, to access users' personal information.

The proposed settlement, which was disclosed in a US court filing late on Thursday, would resolve a long-running lawsuit prompted by revelations in 2018 that Facebook allowed the British political consulting firm Cambridge Analytica to access the data of as many as 87 million users.

Lawyers for the plaintiffs called the proposed settlement the largest to ever be achieved in a US data privacy class action, and the most that Meta has ever paid to resolve a class action lawsuit.

"This historic settlement will provide meaningful relief to the class in this complex and novel privacy case," the lead lawyers for the plaintiffs, Derek Loeser and Lesley Weaver, said in a joint statement.

Meta did not admit wrongdoing as part of the settlement, which is subject to the approval of a federal judge in San Francisco.

The company said in a statement that settling was "in the best interest of our community and shareholders."

"Over the last three years we revamped our approach to privacy and implemented a comprehensive privacy program," Meta said.

Cambridge Analytica, now defunct, worked for Donald Trump's successful presidential campaign in 2016, and gained access to the personal information from millions of Facebook accounts for the purposes of voter profiling and targeting.

The company obtained that information without users' consent from a researcher who had been allowed by Facebook to deploy an app on its social media network that harvested data from millions of its users.