Poland’s parliament has voted in favour of a bill that would force Discovery Inc, the US owner of Poland’s largest private television network, to sell its Polish holdings.

The bill, if it gets the Polish president’s approval, is widely viewed as a blow to media independence in Poland

The draft legislation would prevent non-European owners from having controlling stakes in Polish media companies.

In practice, it only affects TVN, which includes TVN24, an all-news station that is critical of the nationalist right-wing government and has exposed wrongdoing by Polish authorities.

Legislators voted 228-216 to pass the legislation, with 10 abstentions.

The bill must still go to the Senate, where the opposition has a slim majority.

The upper house has much less power and can suggest changes but the lower house can ultimately pass it as it wishes. It will then go to President Andrzej Duda, an ally of the right-wing government.

Discovery said it was “extremely concerned” and appealed to the Senate and Mr Duda to oppose the project.

“Poland’s future as a democratic country in the international arena and its credibility in the eyes of investors depend on this,” it said.

The vote in parliament followed two days of political upheaval that saw the prime minister on Tuesday fire a deputy prime minister who opposed the media bill.

The ruling party appeared earlier on Wednesday not to have the votes, but apparently found them after all.

There was also tension on the street after the vote, with protesters gathering in front of parliament. Some clashed with police and were detained.

The media bill is viewed as a crucial test for the survival of independent news outlets in the former communist nation, coming six years into the rule of a populist government that has chipped away at media and judicial independence.

The ruling party has long sought to nationalise media in foreign hands, arguing it is necessary for national security.

Ejecting TVN’s American owner from Poland’s media market would be a huge victory for the government, coming after the state oil company last year bought a large private media group.

Its political opponents, however, believe that TVN’s independence is tantamount to saving media freedom and see the survival of Poland’s democracy as being on the line.

TVN’s all-news station TVN24 is a key source of news for many Poles but it is also a thorn in the government’s side.

The government’s supporters consider it biased and unfairly critical.

Ahead of the vote, State Department spokesman Ned Price said the matter was being closely watched by US President Joe Biden’s administration.

“When it comes to the media, we know that a free and independent media makes our democracies stronger, it makes our transatlantic alliance more resilient, including to those who would seek to divide the alliance and divide us,” he said.

“And it is a fundamental component of our bilateral relationship with Poland. And that is why we have urged the government of Poland to demonstrate its commitments to these principles.”