Donald Tusk told reporters the decision ultimately rests with the courts, but reiterated Warsaw’s opposition to the pipelines, which it says deepened Europe’s reliance on Russian energy.
“The problem of Europe, the problem of Ukraine, the problem of Lithuania and Poland is not that Nord Stream 2 was blown up, but that it was built,” Tusk said.
“It is certainly not in Poland’s interest to hand over this citizen to a foreign country," he added.
The suspect, identified only as Volodymyr Z., was detained near Warsaw in late September.
A Polish court ruled on Monday that he must remain in custody for another 40 days while judges decide whether to transfer him to Germany under a European arrest warrant.
His lawyer, Tymoteusz Paprocki, told public broadcaster Polish Radio last week that his client had done nothing wrong and would plead not guilty.
The lawyer argued that, given Russia's war in Ukraine, damaging infrastructure owned by a Russian state-controlled company should not be considered a crime.
Lawyer Tymoteusz Paprocki. Photo: PAP/Marcin Obara
German authorities believe the man, a diving instructor, was directly involved in the blasts.
German prosecutors have said he was part of a group suspected of renting a sailboat and planting explosives on the pipelines near the Danish island of Bornholm in September 2022.
He faces charges of conspiring to commit an explosives attack and “anti-constitutional sabotage,” according to a report by the Reuters news agency.
In August, Italian police arrested another Ukrainian suspected of coordinating the attacks.
Swedish and Danish investigators said in 2022 that the blasts on the Nord Stream 1 and 2 pipelines were an act of sabotage after traces of explosives were found at the site.
The explosions ruptured three of the four pipelines on the Baltic seabed and cut most Russian gas supplies to Europe.
European officials said at the time that Russian naval vessels had been spotted near the site, though Moscow has denied responsibility and blamed the West.
Ukraine has also denied involvement.