- In the latest escalation of their dispute, Polish judges ruled, in a case brought by the country's prime minister, that national law has primacy over European rules.
- Opinion polls show that Polish voters are overwhelmingly pro-European — a far cry from Britain which voted to leave the EU in 2016.
- And the Polish government also claims to be supportive of the EU project. But its actions does raise questions about whether that's really true.
Poland's highest court has ruled that some EU laws conflict with the country's own constitution — a move that has raised concerns about Poland's commitment to the Union.
The European Commission, the executive arm of the EU, and the conservative government in Poland have clashed for several years over the rule of law. Brussels has accused Warsaw of undermining the independence of the judicial system and has so far held back on deciding whether to disburse post-pandemic recovery funds worth about 30 billion euros ($34 billion).
In the latest escalation of their dispute, Polish judges ruled, in a case brought by the country's prime minister, that national law has primacy over European rules.
Get San Diego local news, weather forecasts, sports and lifestyle stories to your inbox. Sign up for NBC San Diego newsletters.
"The Polish Constitutional Court is not the first European court to question the principle of the primacy of EU law over national law. However, it is the first time that comes from an illegally composed Court and in those rebellious terms," Alberto Alemanno, a professor of European law at H.E.C. Paris, told CNBC via email.
"This frontal attack is set to backfire both in the EU, where the national recovery plan will remain unapproved, and in Poland, where Poles will start questioning their government's stance in the EU," he added.
Opinion polls show that Polish voters are overwhelmingly pro-European — a far cry from Britain which voted to leave the EU in 2016.
And the Polish government also claims to be supportive of the EU project. But its actions does raise questions about whether that's really true.
"It's hard to believe the Polish authorities and the (ruling) PiS Party when they claim that they don't want to put an end to Poland's membership of the EU," Jeroen Lenaers, a member of the European Parliament and spokesman for the largest political group in that chamber, said in a statement.
"This is an attack on the EU as a whole," he added following the court ruling.
France's European Affairs Minister Clément Beaune also said Friday that the decision out of Poland was "very serious" and adds to the risk of a possible exit from the bloc.
The Polish government was not available for comment when contacted by CNBC on Friday.
The commission, on the other hand, said it "will not hesitate to make use of its powers under the Treaties to safeguard the uniform application and integrity of Union law."
In the worst escalation possible, the commission could propose that Poland loses its voting rights in the EU. This would have to be approved by a qualified majority among the other EU members.
"I am deeply concerned by yesterday's ruling of the Polish Constitutional Tribunal," European Commission President Ursula von der Leyen said in a statement Friday.
"Our Treaties are very clear," she said, "EU law has primacy over national law, including constitutional provisions.