Warsaw - EU President Donald Tusk has warned that Poland's right-wing government could try to drive the country out of the European Union if it stops being a net recipient of bloc funding.

The former liberal Polish premier and arch-rival of the governing Law and Justice (PiS) party spoke at a time when Poland is mired in conflict with the EU over various issues, including the controversial judicial reforms that led Brussels to launch unprecedented disciplinary proceedings against Warsaw last month.

"For PiS the benefit of being in the EU boils down to the balance of payments, with a complete disregard for other benefits like the common market, legal order, guaranteed security, etc," Tusk told the Tygodnik Powszechny news weekly in an interview published Wednesday.

"As long as we're not a net contributor, the game is worth the candle for them. So I can easily imagine a situation where if one day Poland finds itself among the (net) contributors, the Polish government will decide that it's time to ask Poles if they still want Poland in the EU and then will work hard so that they come to the conclusion that it's necessary to say goodbye to membership."

This week the country's new Prime Minister Mateusz Morawiecki sacked his defence and foreign ministers in a major cabinet reshuffle and met with European Commission President Jean-Claude Juncker as part of the governing party's quest to mend the strained ties.

Tusk said it was "a sad day for all" last month when Brussels triggered article seven of the EU treaty over what it sees as "systemic threats" to the independence of the Polish judiciary from the nation's right-wing government.

Never before used against an EU member state, the proceedings can eventually lead to the "nuclear option" of the suspension of a country's voting rights within the bloc.

But Tusk said "the PiS can still end this crisis by abandoning the changes to the judiciary."

The PiS government began making the changes after coming to power in late 2015 and says the reforms are needed to combat corruption and overhaul the judicial system still haunted by the communist era.

Brussels has repeatedly warned that it views the changes as a threat to the democratic principles and rule of law Poland signed up to when it joined the EU.

"In Brussels there's still a huge surplus of hope -- I'm not saying trust, that unfortunately vanished already -- that Poland will nevertheless remain in the EU," Tusk said.