In summer/autumn 2025, Italian and Polish courts ruled on European Arrest Warrants (EAWs) issued by Germany for the criminal prosecution of Ukrainian nationals allegedly involved in the attacks on the North Stream Pipeline in the Baltic Sea on 26 September 2022. Given that the acts may have undermined the internal security of the Federal Republic of Germany and due to the particular importance of the case, the investigations in Germany are conducted by the Federal Public Prosecutor General (Generalbundesanwalt). The Office of the Federal Prosecutor General has investigated seven Ukrainians. According to their findings, the Ukrainians chartered a yacht and placed explosive devices on the Nord Stream 1 and 2 gas pipelines in the Baltic Sea in September 2022. Several explosions damaged the two pipelines so badly that gas could no longer be transported from Russia to Europe. The Federal Prosecutor General issued arrest warrants for anti-constitutional sabotage committed concurrently with causing an explosion and with destruction of buildings and structures (Sections 88, 305, and 308 of the German Criminal Code).

The courts reached different decisions on the EAWs, which sparked a legal debate on fundamental issues of the EU's extradition scheme under the Framework Decision on the European arrest warrant (FD EAW). These issues include the competence to prosecute potential criminal acts in international waters, the scope of the examination of double criminality requirements, the justification of the act as an anti-war operation, immunity, the political offence exception, and procedural safeguards and fair trial. In detail, the extradition proceedings proceeded as follows:

• In Poland: On 17 October 2025, the Regional Court in Warsaw refused to extradite 46-year-old Ukrainian Volodymyr Z. and lifted his pre-trial detention. The court justified its decision primarily on the following grounds: Firstly, any action taken would have been within the framework of a just defensive war on behalf of Ukraine, meaning the suspect did not commit a crime under Polish law, and therefore double criminality was not established (Article 607r §1(1) of the Polish Code of Criminal Procedure). Secondly, the German state does not have jurisdiction to prosecute any natural person for causing the explosion of the pipelines; jurisdiction would lie with an international tribunal adjudicating armed conflicts at sea, or with an ad hoc tribunal appointed by the UN to judge the incident in question. Polish Prime Minister Donald Tusk stated that "the case is closed now" and that it was not in his country's interest to prosecute or extradite the man.
• In Italy: On 15 October 2025, the Italian Supreme Court overturned a decision by the Bologna Court of Appeal that had authorised the surrender of Serhij K., suspected by German investigators to be mastermind behind the attack. The Italian Supreme Court objected to the Bologna court's reclassification of the offence in the German EAW, which aimed to apply tighter procedural rules for terrorists in the extradition proceedings (for an in-depth analysis of the Supreme Court's decision →N. Canestrini, "(Non-)Extradition in the Nord Stream Case and the Limits of Executing State Authority in Mandatory European Arrest Warrant Proceedings", https://doi.org/10.30709/eucrim-2025-019). After remittal of the case, the Bologna Court of Appeal reordered K.'s surrender to Germany on 23 October 2025. In this second ruling, the Bologna court addressed the procedural defect that had invalidated the previous proceedings, but did not substantively revisit key refusal grounds put forward by the defence, such as functional immunity, ne bis in idem, and risks of violations of Art. 3 ECHR. A second appeal against this decision was dismissed by the Italian Supreme Court on 19 November 2025, which confirmed the surrender order. K was effectively surrendered on 27 November 2025.
• In Germany: On 15 January 2026, the Federal Court of Justice (FCJ, Bundesgerichtshof) dismissed a complaint against the order for arrest filed by Serhij K., following his extradition from Italy. The FCJ affirmed both the strong suspicion of a criminal offence falling within the Federal Public Prosecutor General’s jurisdiction and the risk of flight as reasons for arrest. It rejected the defendant's arguments of immunity and of "combatant privilege" for justification of the act. Lastly, the FCJ stated that Germany has territorial jurisdiction because the result of the offence – the pipelines being rendered inoperable – also occurred on German territory, where the pipelines ended.

In the Nord Stream extradition case complex, courts in different EU countries approached the legal grounds for refusing the European Arrest Warrants differently. This is particularly interesting in cases such as Nord Stream that have political and military backgrounds and raise legal questions regarding the relationship between the EAW and international public law.