London (AFP) - Unregulated online content has spread disinformation and propaganda that have amplified political divisions, fanned international tensions and even contributed to Russia's invasion of Ukraine, a media watchdog said Tuesday.

Reporters Without Borders, widely known by its French acronym RSF, presented its findings in the 2022 edition of its annual World Press Freedom Index.

Democratic societies, it said, are increasingly fractured by social media spreading disinformation and media pursuing a "Fox News model", referring to the controversial US right-wing television network.

Autocratic regimes meanwhile tightly control information within their societies, using their leveraged position to wage "propaganda wars" against democracies and fuel divisions within them.

Such polarisation is becoming more "extreme," worldwide, RSF's director of operations and campaigns Rebecca Vincent told a news conference in London.

She pointed to the deaths of journalists in the Netherlands and Greece as well as the case of Julian Assange, the WikiLeaks founder who risks extradition and trial in the US for the publication of secret files.

The report showed how Russia, where state-run media overwhelmingly dominates and independent outlets are largely stifled, waged a propaganda war before its invasion of Ukraine.

Evgeniya Dillendorf, a correspondent for the independent Novaya Gazeta newspaper, said the main reason for lack of media diversity in Russia "is not pressure but lack of independent business which would finance it, and the lack of independent judicial system that would defend it".

Novaya Gazeta has suspended publication for the duration of Moscow's military intervention to avoid being shut down.

"The creation of media weaponry in authoritarian countries eliminates their citizens' right to information but is also linked to the rise in international tension, which can lead to the worst kind of wars," RSF Secretary-General Christophe Deloire said.

The "Fox News-isation" of Western media also posed a "fatal danger for democracies because it undermines the basis of civil harmony and tolerant public debate", he added.

Deloire urged countries to adopt legal frameworks to protect democratic online information spaces.

Record 'very bad'

The situation is "very bad" in a record 28 countries, according to this year's ranking of 180 countries and regions.

The lowest ranked were North Korea (180th), Eritrea (179th) and Iran (178th), with Myanmar (176th) and China (175th) close behind.

Russia (155th) and its ally Belarus (153rd) were also among the most repressive.

Based on the previous calendar year, this does not reflect Russia's massive media crackdown since President Vladimir Putin sent troops into Ukraine.

Hong Kong's position plummeted dozens of places to 148th, reflecting Beijing's efforts to use "its legislative arsenal to confine its population and cut it off from the rest of the world", RSF said.

"It is the biggest downfall of the year, but it is fully deserved due to the consistent attacks on freedom of the press and the slow disappearance of the rule of law in Hong Kong," Cedric Alviani, head of RSF's Taiwan-based East Asia bureau, told AFP.

Just eight countries were ranked as "good", down from 12 last year.

Nordic countries Norway, Denmark and Sweden again topped the index, while the Netherlands fell from sixth to 28th after top crime reporter, Peter R. de Vries, was gunned down on an Amsterdam street last July.

The Free Press Unlimited group called the fall in the Netherlands "alarming news" and unprecedented, as the country had always been in the top 10 since 2002.

RSF commended Moldova (40th) and Bulgaria (91st) this year due to government changes and "the hope it has brought for improvement in the situation for journalists". 

But it noted "oligarchs still own or control the media" in both.

Media polarisation was "feeding and reinforcing internal social divisions in democratic societies" such as the United States (42nd), it said.

That trend was even starker in "illiberal democracies" such as Poland (66th), a European Union country where RSF noted suppression of independent media.

The NGO, launched in 1985 and which has published the yearly index since 2002, has become a thorn in the side of autocratic and despotic regimes around the world.

This year's listing used five new indicators to define press freedom -- political context, legal framework, economic context, sociocultural context, and security -- to reflect its "complexity".