FILE PHOTO: The International Criminal Court building is seen in The Hague, Netherlands, January 16, 2019. REUTERS/Piroschka van de Wouw/File Photo
European Union flags fly outside the European Commission headquarters in Brussels, Belgium, March 1, 2023.REUTERS/Johanna Geron/File Photo

By Stephanie van den Berg and Charlotte Van Campenhout

BRUSSELS/THE HAGUE (Reuters) -The EU gave its backing on Friday to the International Criminal Court after Washington imposed sanctions on four ICC judges, and EU member Slovenia said it would push Brussels to use its power to ensure the U.S. sanctions could not be enforced in Europe.

"The ICC holds perpetrators of the world’s gravest crimes to account and gives victims a voice. It must be free to act without pressure," European Commission President Ursula Von der Leyen said on social media platform X.

Antonio Costa, president of the European Council, which represents national governments of the 27 member states, called the court "a cornerstone of international justice" and said its independence and integrity must be protected.

U.S. President Donald Trump's administration imposed sanctions on four judges at the ICC in retaliation for the war tribunal's issuance of an arrest warrant for Israeli Prime Minister Benjamin Netanyahu and a past decision to open a case into alleged war crimes by U.S. troops in Afghanistan.

The U.S. order names Solomy Balungi Bossa of Uganda, Luz del Carmen Ibanez Carranza of Peru, Reine Adelaide Sophie Alapini Gansou of Benin and Beti Hohler of Slovenia.

The U.S. sanctions mean the judges are now on a list of specially designated sanctioned individuals. Any U.S. assets they have will be blocked and they are put on an automated screening service used by not only American banks but many banks worldwide, making it very difficult for sanctioned persons to hold or open bank accounts or transfer money.

Trump's initial order announcing sanctions on the ICC also said that U.S. citizens who provide services for the benefit of sanctioned individuals could face civil and criminal penalties.

Slovenia urged the EU to use its blocking statute, which lets the EU ban European companies from complying with U.S. sanctions that Brussels deems unlawful. The power has been used in the past to prevent Washington from banning European trade with Cuba and Iran.

"Due to the inclusion of a citizen of an EU member state on the sanctions list, Slovenia will propose the immediate activation of the blocking act," Slovenia's foreign ministry said in a post on social media site X late on Thursday.

ICC president Judge Tomoko Akane had urged the EU already in March this year to bring the ICC into the scope of the blocking statute.

The new sanctions have been imposed at a difficult time for the ICC, which is already reeling from earlier U.S. sanctions against its chief prosecutor, Karim Khan, who last month stepped aside temporarily amid a United Nations investigation into alleged sexual misconduct.

The court's governing body, which represents its 125 member states, on Friday condemned the U.S. government's decision to retaliate against judges.

"These ... are regrettable attempts to impede the Court and its personnel in the exercise of their independent judicial functions", the Presidency of the Assembly of States Parties said.

(Reporting by Stephanie van den Berg in The Hague and Charlotte Van Campenhout, Editing by Benoit Van Overstraeten, William Maclean)