BRUSSELS (Reuters) - The European Commission decided this week to take Poland to the top European Union court over court reforms the EU says could threaten the independence of the Polish judiciary, a senior EU official said.

Poland will be referred to the EU Court of Justice for its reform of the Supreme Court. Warsaw argues the changes were legal.

The Commission’s move is the third step in a lengthy procedure to sanction member states who breach EU law.

The procedure is meant to put pressure on the offending member states and could eventually end with financial sanctions, although this has occurred only in rare cases.

The EU executive has taken its decision but postponed announcing it to Monday, Sept. 24, to avoid interfering with an informal summit of European Union leaders in Austria this week, the official told Reuters.