Warsaw has warned that it could veto the bloc’s 2021-2027 budget if access to EU funds is linked to respect for the rule of law.
Premier Mateusz Morawiecki put forward Poland’s case at a video summit of EU leaders on Thursday evening.
Government spokesman Piotr Müller said that Morawiecki had maintained Poland's opposition to the introduction of “arbitrary and non-objective criteria determining the disbursement of budget funds".
Müller added the Polish prime minister "indicated that the proposed rules are inconsistent with the EU treaties and the conclusions of the European Council of July."
Thursday’s meeting of EU leaders did not resolve differences over the planned new rule-of-law mechanism, Polish state news agency PAP reported.
Polish deputies on Thursday passed a resolution supporting the government's stance on negotiating the EU’s next budget.
The resolution voiced opposition to any mechanism that contains "unclear, imprecise" rules that could be "interpreted in a biased way".
At a meeting in Brussels on Monday, ambassadors from EU governments by a majority of votes approved a mechanism to make the pay-out of the bloc’s funds conditional on member states’ adherence to the rule of law.
Poland and Hungary have denied EU accusations of violating democratic principles and undermining the independence of their courts.
The EU budget must be approved unanimously by the bloc’s 27 member states.