Pro-government media in Serbia reacted with outrage on Thursday to a decision by Twitter to label most outlets "state-affiliated", with one newspaper comparing the social media platform to Adolf Hitler.

Twitter accounts of most influential newspapers and all national TV broadcasters, including public service Radio-television of Serbia (RTS), were marked as linked to the Serbian government earlier this week.

Twitter defines state-affiliated media as outlets where the state "exercises control over editorial content through financial resources, direct or indirect political pressures, and/or control over production and distribution".

Serbia's ruling party led by populist President Aleksandar Vucic faces growing accusations from rights groups that it is snuffing out critical journalism and consolidating media ownership into friendly hands.

Vucic said the decision to label the media state-affiliated was a "compliment" for those outlets, adding that it was normal for media outlets to collaborate with the government.

"Now you see who the real censors are. I can't wait for them to suspend my account, so I can become another Trump in the world," Vucic told local media.

Radio-television of Serbia called the decision political and said it would stop posting on Twitter altogether in protest.

Pro-government tabloid Informer on Thursday published a front page headline dominated by a photo of Adolf Hitler, calling Twitter a "propaganda war machine".

The European Parliament recently warned of deteriorating media freedoms in the Balkan country, while Reporters Without Borders (RSF) noted that independent journalists in Serbia are subjected to almost daily attacks from pro-government media.

"Serbia is a country with weak institutions that is prey to fake news spread by government-backed sensational media," RSF said in their 2021 report.

Last year, Twitter deleted over 8,500 accounts who coordinatedly posted some 43 million tweets criticising Serbian opposition and country's independent media.