WASHINGTON — A small Ukrainian crew disguised as a pleasure boat cruise was behind the sabotage of the Nord Stream pipelines, according to a report by the Wall Street Journal.

The operation was concocted during a drunken night in May 2022, as Ukrainian military officers celebrated halting Russia's full-scale invasion of the country and were looking to deal another blow to Moscow, the newspaper said, citing four anonymous sources familiar with the plan.

Nord Stream is a network of pipelines running under the Baltic Sea from Russia to Germany to provide Western Europe with natural gas, meaning it provided billions to the Kremlin's coffers.

The scheme reportedly cost around $300,000 (€273,000) and involved a six-member crew on a small rented yacht. Ukrainian President Volodymyr Zelenskyy initially approved it before the US intelligence agency CIA caught wind and asked him to stop.

The Ukrainian president ordered a halt but his commander-in-chief, Valeriy Zaluzhniy, went ahead with the operation anyway, the WSJ said.

The outlet said it had spoken to four senior Ukrainian defense and security officials who either participated in or had direct knowledge of the plot and that all of them considered the pipelines as a legitimate target as it defended itself against Russia.

Euronews could not independently verify the claims made by these sources.

The WSJ also said that portions of the sources' accounts had been corroborated by a German investigation into the matter.

Yet, German intelligence officials have said that they doubt that Ukraine was really behind the sabotage and that it's possible it was a "false flag" operation by Russia.

This is supported by Polish authorities who sent the names of Russian suspects to Germany's intelligence service.

The WSJ article comes after German media reported that prosecutors had issued the first arrest warrant in their investigation into the Nord Stream attack. The report identified the man as Volodymyr Z, without citing sources, and suggested he had recently returned to Ukraine.

Polish authorities have since revealed they attempted to arrest Volodymyr Z at his address in a town near Warsaw in July but that he had already gone back to his native country.

He wasn't stopped at the Polish-Ukrainian border because German authorities failed to enter his name in the wanted database, the Polish prosecutor's office said on Wednesday.

German reports also named two other suspects: married couple Svitlana and Yevhen Uspenska, who run a diving school in Ukraine.

They have both denied being involved in the attack, as their maximum diving depth is 30 meters, compared to the approximately 80 meters at which the explosions happened. — Euronews