Nord Stream Sabotage Trial: What to Know as Germany Prosecutes Ukrainian Suspect

German prosecutors are bringing the first formal case to court over the 2022 sabotage of the Nord Stream natural gas pipelines. The trial begins Wednesday in Hamburg, centering on accusations that Ukrainian military personnel orchestrated the explosions beneath the Baltic Sea.

Here is what to know about the case, the suspect, and the geopolitical fallout.

What is the Nord Stream pipeline?

Nord Stream is an offshore network connecting Russia and Germany beneath the Baltic Sea. The four lines of Nord Stream and Nord Stream 2 had a combined annual capacity of 110 billion cubic meters. Construction on the first line finished in 2011, while Nord Stream 2 was completed in September 2021 but never opened.

In September 2022, operator Nord Stream AG confirmed major damage after Danish and Swedish authorities reported explosions and gas leaks. Russia opened an international terrorism case, and President Vladimir Putin pointed to the United States, Ukraine, and Poland as beneficiaries of the disruption.

What are the charges against the suspects?

A Ukrainian national identified as Serhii K. faces trial in Hamburg. Authorities detained him near Rimini, Italy, in August 2025 and extradited him three months later.

Prosecutors charge Serhii K. with causing an explosion, property damage, public service disruption, and acting as an accomplice to war crimes for targeting civilian objects. Investigators allege he served as a Ukrainian army officer and helped lead a cell that planted HMX and RDX explosives from a hired yacht named the Andromeda.

A second suspect, Vladimir Z., remains in Croatia fighting extradition after earlier detention in Poland. Serhii K. denies all allegations.

How have governments responded?

The investigation has strained diplomatic ties across Europe and North America. Moscow dismissed early Western suspicion of Russian involvement as absurd, noting Russia lost its primary export route.

The U.S., Poland, and the U.K. have denied any involvement. Ukrainian President Volodymyr Zelenskyy has repeatedly denied state participation, stating that German officials were briefed on Kyiv’s lack of involvement.

Meanwhile, Polish Prime Minister Donald Tusk argued that Germany should not prosecute suspects who disabled the contentious energy infrastructure, saying builders of the project should be ashamed instead.