In this undated file photo, the European Union flags in front of EU headquarters in Brussels, Belgium. (PHOTO / XINHUA)

WARSAW - The European Union's top court said on Thursday that Poland's Chamber of Extraordinary Control and Public Affairs of the Supreme Court was not an independent tribunal under EU law.

The Chamber, created as part of nationalist Law and Justice (PiS) party reforms of the judiciary, is responsible, among other things, for ruling on the validity of national elections including those of Oct 15, as a result of which PiS lost power.

A new pro-European government led by Donald Tusk, former European Council president, has vowed to undo the changes made to Poland's judiciary by the Law and Justice party

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Critics and European institutions have repeatedly criticized those reforms and Brussels froze billions of euros in EU funds for Poland over rule of law concerns.

A new pro-European government led by Donald Tusk, former European Council president, has vowed to undo the changes and obtain access to the money as soon as possible.

The Court of Justice of the EU said in its ruling that the way judges were appointed to the chamber under new rules introduced by PiS was illegal, therefore a request for a preliminary ruling from the chamber was inadmissible.

"Due to circumstances relating to the appointment of the judges of the Extraordinary Control and Judicial Chamber of the Polish Supreme Court, the formation of that Chamber is not a 'court' within the meaning of EU law," the Court said.

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"Consequently, the Court does not examine the substance of the questions referred by that body."