Poland's Prime Minister has warned that overreach by some of the EU institutions is a threat to the future of the bloc.

       The European Commission is currently preparing legal action against the Polish government after its top court ruled that some European laws are incompatible with the country's constitution.

       But in a letter to the EU's 27 national leaders, Mateusz Morawiecki defended his country's actions, saying that the Commission is dangerously overstepping the limits of its powers by interfering in Polish constitutional matters.

       "Today we are dealing with a very dangerous phenomenon whereby various European Union institutions usurp powers they do not have under the Treaties and impose their will on Member States," Morawiecki wrote.

       However, pressure is mounting on the European Commission to take action.

       MEPs want it to use a previously unused legal measure, a so-called rule-of-law conditionality mechanism, which allows the suspension of EU funds if a serious misuse of the bloc's budget and pandemic recovery funds is found.

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       The Commission is also withholding approval of Poland's national recovery plan - worth €23.9 billion in grants and €12.1 billion in loans - over the independence of the courts, media freedoms and LGBT rights.

       As these tensions between Brussels and Warsaw increase, the Polish Prime Minister is set to defend his country's actions to MEPs in Strasbourg on Tuesday.

       But Alberto Alemanno, a professor of EU Law & Policy at HEC Paris, told Euronews that anything he does say to European lawmakers will likely ring hollow.

       "There's a great majority of the Parliament saying 'Hey Commission - don't approve this national plan.' But now we feel that the Commission, because of Merkel, is pushing for appeasement [of Poland] and saying, let's approve the national plan, but activate the conditionality regulation in the new infringement proceedings against the constitutional court, so I think this is the game," Alemanno said.

       Morawiecki did hint in his letter that Poland is willing to de-escalate the situation through talks, which could come at this week's European leaders summit.