San Francisco, Feb 9 (IANS): A US-based news organisation has filed a lawsuit against Facebook and Alphabet, the parent company of Google, alleging that the tech giants with their dominance over the digital advertising market adversely affected an important revenue source.

The lawsuit makes the argument the Google and Facebook represent a digital monopoly that should be broken up, The Verge reported on Monday.

"Google and Facebook have monopolised the digital advertising market thereby strangling a primary source of revenue for newspapers across the country," according to the complaint filed by HD Media.

HD Media operates Charleston Gazette-Mail, The (Huntington) Herald-Dispatch and several other West Virginia newspapers.

The organisation filed a complaint in the United States District Court for the Southern District of West Virginia.

The complaint also alleges that Facebook and Google violated antitrust laws in the US by attempting to consolidate their dominance of the digital advertising market, striking a secret pact codenamed "Jedi Blue" to manipulate online auctions.

Google spokesperson Peter Schottenfels called it "mischaracterisations about our Open Bidding agreement with Facebook," said The Verge report.

"The freedom of the press is not at stake," the suit said.

"The press itself is at stake."

The move comes at a time when Australia is planning a new law to make Google and Facebook pay for displaying news.

According to a report in the Financial Times on Monday, lawmakers in the European Union are also considering a similar move.