People in Poland have taken to the streets to support the country's membership in the European Union. Protests erupted after the country's top court ruled that key articles of the bloc's laws were against its constitution, sparking fears amongst the public of a possible Polish exit.

Organizers of the protests said over 100,000 people had participated in the protests in the capital city of Warsaw. Similar protests were also being held simultaneously in more than 100 other towns and cities across the country.

Last week, the Supreme Court of Poland officials rejected the core principles outlined in EU law. It added that the bloc's rules do not outweigh national legislation.

Poland's Prime Minister, Mateusz Morawiecki, defended the court's ruling, stating that the rights of the country must be respected just like any other country. Despite his statements, Morawiecki assured the public that Poland's place was to be with its "European family of nations." He said his party has no plans of exiting the union, a move which has now been called "Polexit."

Opposition members and political activists joined in the protests in Poland. In the demonstrations held in Warsaw, activists called on the people to defend a "European Poland."

The former president of the European Council and leader of the opposition party Civic Platform, Donald Tusk, told protesters that they must not allow Poland to exit the European Union.

Leaders of EU countries had voiced their concerns over Poland's ruling that some parts of the bloc's laws were unconstitutional. Politicians said the ruling undermined the legal pillar on which the member nations abide as part of the EU.

The president of the European Commission, Ursula von der Leyen, said she was "deeply concerned" about Poland's actions and added that she would work to make sure that the EU's laws have primacy.

Luxembourg's minister for foreign affairs, Jean Asselborn, said Poland has to acknowledge that it is effectively "playing with fire" with what it is insinuating.

"The primacy of European law is essential for the integration of Europe and living together in Europe. If this principle is broken, Europe as we know it, as it has been built with the Rome treaties, will cease to exist," Asselborn said.