New York, Oct 27 (IANS): German Chancellor Angela Merkel has accused technology giants Facebook and Google of "narrowing perspective" and demanded that they make public their privately-developed algorithms, media reported.

Merkel, who had previously blamed the social media for anti-immigrant sentiment, said: "The algorithms must be made public, so that one can inform oneself as an interested citizen on questions like, 'what influences my behaviour on the internet and that of others?'."

"These algorithms, when they are not transparent, can lead to a distortion of our perception, they narrow our breadth of information," RT.com quoted Merkel as saying in Berlin this week.

Google and Facebook use algorithms to decide which search results are shown first and the order of the news feed respectively.

The companies decide to include posts from a user's liked pages and friends and also promote links to news articles, often based on a user's own media interests.

According to the report, these algorithms comprise some of the most highly-protected trade secrets in the world, potentially worth billions. No internet giant has ever revealed its inner workings.

"The big internet platforms, via their algorithms, have become an eye of a needle which diverse media must pass through to reach users. This is a development that we need to pay careful attention to," Merkel noted.