Poland’s constitutional tribunal has ruled that some EU laws are in conflict with the country’s constitution, taking a major step towards a “legal Polexit” with far-reaching consequences for Warsaw’s funding and future relations with the bloc. The tribunal, whose legitimacy is contested after multiple appointments of judges loyal to the ruling nationalist Law and Justice (PiS) party, said some provisions of EU treaties and EU court rulings clashed with Poland’s highest law, adding that EU institutions “act beyond the scope of their competences”. “This is a legal revolution,” said René Repasi, professor of international and European law at Erasmus university in Rotterdam. “Admittedly it’s a captured court, but this is furthest step towards a legal exit from the EU ever taken by a national court.” In a strongly-worded initial reaction, the European Commission said the decision on Thursday raised “serious concerns”. It reaffirmed that “EU law has primacy over national law, including constitutional provisions”. The commission added that rulings by the European court of justice are “binding on all member state’s authorities, including national courts”, and said it would “not hesitate to make use of its powers under the treaties to safeguard the uniform application and integrity of union law”. Despite opinion polls showing more than 80% of Poles back EU membership, Poland’s PiS-led government is embroiled in a lengthening and increasingly acrimonious series of disputes with the 27-member bloc on questions ranging from judicial reforms and media freedoms to LGBT rights. The Polish prime minister, Mateusz Morawiecki, brought the case in March, arguing Brussels has no right to interfere with the judicial systems of EU member states and the government’s reforms were needed to remove communist-era influences. Warsaw denies having any influence over court decisions but the government has been widely accused of politicising the courts, including the tribunal, which began hearing the case in August but had twice deferred its decision. The primacy of European laws over national ones is a key tenet of European integration and Polish opposition politicians have repeatedly said challenging it jeopardises Poland’s long-term future in the EU and also the stability of the bloc itself. The court decision was widely seen as unsurprising in Brussels. Already embroiled in multiple conflicts with Poland over EU law, EU authorities are keen to avoid raising the temperature with Warsaw and will wait to see what the government does next. But the ruling heightens tensions over Poland’s €57bn (£48bn) in EU recovery funds, yet to be approved by Brussels. “EU states must not stand by idly when the rule of law continues to be dismantled by the Polish government,” said Jeroen Lenaers of the European People’s Party, the centre-right bloc in the European parliament. “Neither can the European Commission. Our money can’t finance governments which mock and negate our jointly agreed rules. By declaring that the EU treaties are not compatible with Polish law, the illegitimate constitutional tribunal in Poland has put the country on the path to Polexit,” he said. The Polish government spokesman, Piotr Müller, however, tweeted that the “primacy of constitutional law over other sources of law results directly from the constitution of the Republic of Poland. Today (once again) this has been clearly confirmed by the constitutional tribunal.” Müller added that the ruling “does not affect any areas where the EU has competences delegated in the treaties” such as competition rules, trade and consumer protection. Daniel Freund, a German Green MEP who sits on the European parliament’s budgetary committee, also said Poland was “saying goodbye to the European legal order”. The EU “cannot transfer billions to a member state without being able to legally ensure that the money reaches those for whom it is intended”, he said. The EU economy commissioner, Paolo Gentiloni, last month said the case could have “possible consequences” for Poland’s recovery funds, remarks Warsaw called “blackmail”. EU officials have since said that the money could be paid next month, but with strict rule of law conditions. The Commission last month also asked the court of justice of the EU to impose daily fines on Poland until it suspends its judicial reforms. The European parliament last month adopted a resolution calling on Morawiecki to drop the case, stressing the “fundamental nature of primacy of EU law as a cornerstone principle of EU law”. Two judges on the tribunal dissented from the decision, but a majority said Poland’s EU membership did not give EU courts supreme legal authority, and did not mean Poland had shifted its sovereignty to the EU. No state authority in Poland could consent to external limitation of its powers, they said. Representatives of the country’s human rights commissioner argued, however, that Poland had agreed to respect the EU legal order when it joined the bloc in 2004. “It’s a confederation of anti-democratic forces against Poland’s membership in the European Union,” Michał Wawrykiewicz, a pro-European lawyer critical of the government, tweeted, calling it a “black day” in the country’s history. Laurent Pech, professor of European law at Middlesex university, said Polish authorities had “engineered an (unconstitutional) Polexit from EU legal order” to “establish a Soviet-style justice system so autocratisation can happen undisturbed”.