Facebook has changed some of the procedures it uses for its "Trending Topics" section after it was accused of suppressing conservative views.
Facebook said it will stop looking to a small list of news outlets like The Wall Street Journal, Huffington Post and Drudge Report to automatically nominate topics for its trending feature - and improve staff training.
The company's announcement comes after an internal investigation into bias in the selection of news stories for the section, which is separate from the main News Feed.
Earlier this month, a former Facebook contractor accused the company's editors of deliberately suppressing conservative news.
The allegations were reported by technology news website Gizmodo, which did not identify the ex-contractor.
The report led the US Senate Commerce Committee to write a letter, signed by Republican Sen. John Thune, demanding that the company explain how it selects news articles for the list.
Two days after Senator Thune's letter, Facebook published a lengthy blog post detailing how Trending Topics works even though it rarely discloses such practices.
It had previously never discussed the inner workings of the feature, which displays topics and news articles in the top right hand corner of the desktop homepage for its more than 1.6 billion users.
Facebook said its investigation showed that conservative and liberal topics were approved as trending topics at nearly identical rates.
It said it was unable to substantiate any allegations of politically motivated suppression of particular subjects or sources.
But it said it was introducing several changes, including the elimination of a top 10 list of approved websites, more training and clearer guidelines to help human editors avoid ideological or political bias, and more robust review procedures.
Facebook did not rule out human error in selecting topics.
"Our investigation could not fully exclude the possibility of isolated improper actions or unintentional bias in the implementation of our guidelines or policies," Colin Stretch, Facebook's General Counsel, wrote in a company blog post.
Facebook chief executive Mark Zuckerberg met more than a dozen conservative politicians and media personalities last week to discuss issues of trust in the social network.
(c) Sky News 2016, source Sky News