Poland has missed an EU deadline to respond to concerns over controversial court reforms by the rightwing government, which Brussels fears will erode judicial independence, a Brussels spokesman said Sunday.
On July 26, the European Commission gave Warsaw a month to end what it considers a "systemic threat" to the rule of law and inform the EU executive branch of measures taken to modify the reforms.
"As far as I am aware, we have still not received a response," a commission spokesman told AFP.
The EU executive will meet Monday to consider the issue, he added.
The Polish foreign ministry, for its part, told AFP that "as the deadline falls on a holiday, we consider that it ends on the first working day after that".
The ministry later added that it would send its response on Monday.
Tensions between Warsaw and the EU have been growing over what Brussels sees as a growing threat, not just to democratic standards in Poland but across the 28-nation bloc.
It could eventually lead to a case against Poland before the bloc's highest court, the European Court of Justice, and possibly a fine.
The commission has said the threat to judicial independence comes from the Polish justice minister getting "discretionary power to prolong the mandate of judges who have reached retirement age as well as to dismiss and appoint court presidents."
Other concerns, it said, include "discrimination on the basis of gender" by setting the retirement age at 60 for female judges and at 65 for their male counterparts.
The legal overhauls have triggered mass street protests in Poland and raised fears about the rule of law in one of the EU's leading former communist states in the east.
Brussels and Warsaw have been at loggerheads ever since Poland's governing PiS party announced reforms to the country's constitutional court after coming to power in late 2015.
European Commission First Vice President Frans Timmermans has warned that the commission is ready to immediately trigger the EU's never-used Article 7 procedure -- a so-called "nuclear option" that can freeze a country's right to vote in meetings of EU ministers -- if Supreme Court justices are sacked.
In a separate brewing row, French President Emmanuel Macron on Friday made stinging comments against Warsaw for rejecting tough proposals to overhaul a controversial EU rule on cheap labour.
"Poland today is not a country that can show Europe the way, it's a country that has decided to go against European interests in many areas," Macron told a press conference during a visit to Bulgaria.
"Europe was built on public freedoms that Poland violates," he added. "It is placing itself on the margins of Europe's future history."
The EU has also warned Poland to obey a ban on logging in the ancient forest of Bialowieza, saying it would add any breach to the broader Brussels case against Warsaw over democratic standards.
On Saturday the German weekly Der Spiegel said EU Commission chief Jean-Claude Juncker wanted to suspend Poland's voting rights unless Poland comes into line.