Poland's foreign ministry has said that European standards and the principle of separation of powers were upheld in proposed court reforms which have "prematurely" come under fire in Brussels.

The European Commission on Wednesday said it was ready to take action against Poland for violating EU laws, warning that a controversial overhaul of the country's judicial system threatened the independence of courts.

European Commission Vice-President Frans Timmermans noted that the new set of laws on judicial changes in Poland was not yet in force, but said they would bring the judiciary under the full political control of the government.

The Polish foreign ministry said in a statement on Wednesday that the commission was “premature” because the “process to reform the Polish judiciary has only just begun”, adding that it was ready to keep the commission up to date as the legislative process continued.

The commission's move was the latest in a series of clashes between Brussels and Warsaw. Poland is already embroiled in a row with the EU over sweeping changes to the country’s Constitutional Tribunal and concerns about the rule of law.

Poland’s governing, conservative Law and Justice (PiS) party has criticised Polish courts for taking too long to hear cases and has accused judges of being an elite, self-serving clique, adding that changes are needed to reform an inefficient and sometimes corrupt judicial system.

But thousands of people took to the streets at the weekend in opposition to the proposed changes, accusing PiS of aiming to stack courts with its own candidates and to dismantle the rule of law.

Protesters called the reforms an attack on democracy. PiS denies the accusations.

The Polish parliament on Wednesday debated a bill on appointments to the Supreme Court. (vb/pk)