(Adds quotes from Polish foreign minister, president’s spokesman)

BERLIN, Jan 3 (Reuters) - German Commissioner Guenther Oettinger will urge the European Union to start a process against Poland for threatening its common values with a proposed law on control of state-run media, he told a newspaper on Sunday.

The Polish parliament passed an amendment to the media law, put forward by the ruling conservative-nationalist Law and Justice party (PiS), in December that gives a minister authority to appoint managers of state-run radio and television stations.

It must now be signed by the president to come into force. Critics say the law is part of PiS plans to increase state control over the media.

Oettinger said he would argue the case for using a mechanism designed to tackle concerns about infringement of European values at a meeting of the European Commission on Jan. 13.

“There is a lot to be said for activating the mechanism on the rule of law and putting Warsaw under supervision,” Oettinger, Commissioner for the digital economy, told Germany’s Frankfurter Allgemeine Sonntagszeitung (FAS).

The mechanism was adopted by the EU in 2014 and means it can issue an early warning and enter dialogue with any member state the Commission sees as a threat to the rule of law.

If the country does not respond, the Commission can start a process which could ultimately lead to the withdrawal of its voting rights due to a breach of European values.

The Commission has expressed concern over the media law and is seeking an explanation from Poland of how it would take EU rules on media freedoms into consideration.

The Eurosceptic PiS, which ousted the governing centrist party in October’s election, has rejected criticism that its policies are undermining democracy. It argues that it has a mandate to push for more independence from Brussels.

Polish Foreign Minister Witold Waszczykowski told Germany’s top-selling Bild daily his government wanted to “heal” the country after the previous government’s leftist agenda that had “nothing to do with traditional, Polish values”.

The Polish president’s spokesman told private broadcaster TVN24: “In the last eight years we had no pluralism in the public media at all and no European Commissioner, no member of the European Parliament, deplored it.”

Warsaw has also caused concern in the EU with its amendment to a law on the constitutional court which critics say will erode checks and balances on government powers..

Waszczykowski told Bild he was surprised to have received a letter from Commission Vice-President Frans Timmermans.

“An EU official, who came to office via political connections, writes to a democratically-elected government ... Mr Timmermans is not a legitimate partner for me,” he told Bild. (Reporting by Madeline Chambers; Additional reporting by Wiktor Szary; Editing by Janet Lawrence)