WARSAW, Poland – U.S. President Barack Obama expressed concern Friday about the state of democracy in Poland, publicly rebuking a right-wing government that has paralyzed the constitutional court and taken steps to control state run media.

Obama said he shared his worries with Polish President Andrzej Duda in a one-on-one meeting before the opening of a NATO summit in Warsaw.

“I expressed to President Duda our concerns about certain actions and the impasse around Poland’s constitutional tribunal,” Obama told reporters. “I insisted that we are very respectful of Poland’s sovereignty and I recognized that parliament is working on legislation to take important steps but more needs to be done.”

Poland has been stuck for months in controversy over the 15-member constitutional Tribunal, a body that rules on the constitutionality of legislation, playing a role similar to that of the U.S. Supreme Court. The dispute concerns both appointments to the court and the rules that govern how it functions.

Opponents say the government’s actions undermine democracy and have held several large street protests in recent months. The government’s leaders say it is only trying to correct an imbalance, with appointments by the previous centrist government dominating the court.

The European Union has launched an unprecedented probe into whether Poland is violating the rule of law. The U.S. had expressed some concerns too, but Poles for months have waited to see whether Obama would raise the matter at the summit.

Poland’s parliament on Thursday rushed through legislation governing the constitutional Tribunal in an attempt to address international concerns about the rule of law a day before Obama and other Western leaders arrived in Warsaw. But those in the political opposition strongly criticized the legislative changes as little more than cosmetic. They said the moves do almost nothing to ease concerns over the court, which has been paralyzed by the government and made unable to act as a check on its power. They say that on some points the new legislation is even worse.

Since coming to power last November, the new government has also taken other steps that have raised concerns about other aspects of the rule of law, for example by imposing direct government control on state broadcast media and increasing the state’s surveillance powers over citizens.

“And as your friends and ally we’ve urged all parties to work together to sustain Poland’s democratic institutions,” Obama said. “That’s what makes us democracies, not just by the words written in constitutions or in the fact that we vote in elections, but the institutions we depend on every day, such as rule of law, independent judiciaries and a free press.”

One of Europe’s top human rights officials also spoke out Friday on the controversy surrounding the court.

Nils Muiznieks, the Council of Europe Commissioner for Human Rights, said the new bill passed Thursday “poses a serious threat to the rule of law.”

He had urged Poland to reverse the disputed changes, but said the new legislation “goes in the opposite direction.”