"The political opposition is trying to insinuate that we want #Poland to leave the #EU. This is not just #FakeNews, it is a lie intended to weaken the EU", Morawiecki was quoted as saying by his office on Twitter.
The Polish ruling Law and Justice Party and the opposition have recently accused each other of wanting to withdraw Poland from the EU amid Brussels's criticism of Warsaw's controversial judicial reform which it described as incompatible with EU law.
Last week, the Polish Supreme Court ruled that the national constitution was superior to EU law, prompting an outcry from Brussels.