After tweaking its News Feed to allow users to see more updates from family and friends than posts from businesses, Facebook CEO Mark Zuckerberg has now announced to prioritise news that is trustworthy, informative and local.

In a Facebook post on Saturday, Zuckerberg said it's important that News Feed promotes high-quality news that helps build a sense of common ground for its over two billion users.

Here's how this new update, starting in the US from next week, will work.

"As part of our ongoing quality surveys, we will now ask people whether they're familiar with a news source and, if so, whether they trust that source," the Facebook CEO said.

The idea is that some news organisations are only trusted by their readers or watchers, and others are broadly trusted across society even by those who don't follow them directly, he added.

"To make sure the news you see, while less overall, is high quality. I've asked our product teams to make sure we prioritise news that is trustworthy, informative, and local.

"And we're starting next week with trusted sources," Zuckerberg added.

According to him, the new update will not change the amount of news people see on Facebook. It will only shift the balance of news they see towards sources that are determined to be trusted by the community.

The earlier News Feed update to show more updates from family and friends will result in less public content, including news, video, and posts from brands in your News Feed, he noted.

"After this change, we expect news to make up roughly four per cent of News Feed -- down from roughly five per cent today. This is a big change, but news will always be a critical way for people to start conversations on important topics," the Facebook CEO said.

He said that Facebook has got a feedback from the community that public content -- posts from businesses, brands and media -- is crowding out the personal moments that lead us to connect more with each other.

The impact will vary from Page to Page, driven by factors, including the type of content they produce and how people interact with it.