"I am European. I am also a Pole, but mainly a European," Robert Galemba, a protester, said.
Tens of thousands protested across Poland on Sunday in support of the European Union amid a bitter row with Brussels over the primacy of European over national courts.
A crowd in Warsaw's Castle Square waved European flags and chanted "We are staying" three days after Poland's constitutional court ruled that Polish law superseded European, setting the scene for a battle that could determine whether the country remains in the EU.
Opposition leader Donald Tusk told a crowd in Warsaw that Poland's nationalist government wants to leave the bloc and has engineered the current crisis in order to do so.
Tusk warned that a "pseudo-court ... by order of the party's leader, in violation of the constitution, decided to take Poland out of the EU."
"We know very well why they want to leave the European Union, in fact in order to violate citizens' rights with impunity, to violate democratic principles and to steal without restraint," Tusk said.
Poland's ruling Law and Justice Party leader Jaroslaw Kaczynski denied that he wanted to see a so-called 'Polexit' despite years of wrangling with the EU about his overhaul of the Polish courts, which has seen courts - including the constitutional tribunal - packed with pro-PiS judges.
"I am European. I am also a Pole, but mainly a European," Robert Galemba, a protester, told AP.
"Seventeen years ago, we [...] said in a referendum that we were in favour of being in the Union. I am fed up with the trampling on our common values and what the current government is doing,"
On October 7, the European Commission warned that EU law has primacy over national law - even over a nation's constitution - and European Court of Justice decisions are binding on members.
It said that it would analyse the ruling of the Polish Constitutional Tribunal and "would not hesitate to make use of its powers [...] tp safeguard the unform application and integrity of EU law."
On October 11, a spokesperson told Euronews: "We need to analyse the ruling very carefully. Then, we will decide on the next steps.
"As you can imagine this is an unprecedented situation, where decisions will not be taken lightly. It is clear, however, that we will not hesitate to make use of all our powers under the treaties."
These include financial penalties and the ability to block cash due to Poland under the recovery fund
The row has already seen battle lines drawn between the nations of Western Europe and allies of PiS in the east. France and Germany have both called for sanctions against Warsaw, while Hungary's Viktor Orban has supported the government in Warsaw.
But while many Poles are angered by the government's recent moves, others support it.
"This is not the Union, these are bureaucrats in Brussels. Define what the Union is and what the officials of Brussels are. These are people, not elected by the Member States, right?" Zygmunt Miernik, an opponent of the EU," told AP.
"I do not know where they came from, who created this thing and they appropriate rights that they do not have the right to appropriate, and they want to interfere more and more. I am very happy with the ruling (of the Constitutional Tribunal) that in Poland the constitutional court is most important."