The EU warned Poland it could move closer next month to unprecedented sanctions, unless Warsaw makes "a lot more progress" in the row over its controversial court reforms.
Brussels in December triggered a process that could lead to Warsaw losing its European Union voting rights if it pursues reforms deemed to pose a "systemic threat" to the rule of law.
European Commission Vice President Frans Timmermans on Monday said Poland will face the "full spectrum" of possibilities when European affairs ministers meet again on June 26, days before an EU leaders summit.
"We've made some progress but we still think there is a room for a lot more progress so that we are in a position to say no systemic threat," Timmermans told a news conference.
"It could mean that the Commission (and) Poland make so much progress that we say that there is no longer a systemic threat to the rule of law.
"It could also be on the other side of the spectrum that we do not advance at all anymore, and we have to ask the council to engage in the follow-up phase of Article seven."
"Anywhere between those two most explicit solutions is possibile," the former Dutch foreign minister added, refusing to say June was a deadline.
The next phase would involve the European Council of 28 member states organising a hearing into whether to head further down the path of Article Seven of the EU treaty, which could see Warsaw's voting rights suspended.
Poland's right-wing PiS government began making changes to the judiciary 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 Poland signed up to when it joined the EU.
Sanctions would need unanimous support of all EU members -- except Poland.
Hungary has already said it would veto such a move, but Brussels is hoping the proceedings have significant symbolic power.
Timmermans has welcomed amendments Poland has made in recent weeks to some of its reforms -- including setting the same retirement age for male and female judges.
At the same time the Commission has irked Poland by proposing cutting funding for countries that fail to respect democratic standards in the new multi-annual budget.
European Commission Vice resident Frans Timmermans warned that Poland will face the "full spectrum" of possibilities of sanctions over controversial court reforms