Poland's ruling Law and Justice (PiS) party postponed a parliamentary debate over a new media law, a senior lawmaker said on Wednesday, amid a split with allies over amendments that could see U.S.-owned channel TVN lose its license, Reuters reports.

The proposed legislation would amend Poland's Broadcasting Act and prevent companies from outside the European Economic Area taking control of Polish radio and television stations.

The proposed changes have fueled tensions between Poland and the United States and prompted fresh criticism from Polish opposition groups that the PiS is seeking to curb media freedom.

Officials from the nationalist PiS had signaled the legislation would be discussed at a parliamentary sitting that started on Wednesday, but a senior PiS lawmaker told journalists that the debate would be moved to Aug. 11. "We will not make it during this sitting," said Ryszard Terlecki, the deputy speaker of parliament.

TVN, which is owned by Discovery Inc and has been critical of the government, is one of Poland's biggest TV broadcasters. Its TVN24 outlet is the most popular 24-hour news channel.

The ruling nationalists have long argued that foreign groups own too much of the media in Poland, distorting public debate. Earlier this year, state-run oil refiner PKN bought regional newspaper publisher Polska Press from Germany's Verlagsgruppe Passau, completing a major policy ambition of PiS.

But the party's junior governing ally, the economically-liberal Accord party, has voiced disagreement with the amendments to the Broadcasting Act put forward by the PiS. It has instead proposed that companies from countries belonging to the Organization for Economic Cooperation and Development be allowed to own more than 49% stakes in Polish media companies.

"We will not support this law without the amendment we proposed," Accord spokeswoman Magdalena Sroka told TVN24 on Wednesday.