The European Council has said that the leak in the Nord Stream 2 pipeline is a further attempt to destabilise gas supply to the European Union.
Charles Michel, president of the European Council, said in a statement on Twitter: “Nordstream sabotage acts appear to be an attempt to further destabilize energy supply to EU. We need an urgent and thorough investigation.Those responsible will be held fully accountable and made to pay.”
“Our efforts to diversify energy supply away from Russian gas continue,” Michel said.
Since the Russian invasion of Ukraine in February, the Nord Stream pipelines have been at the centre of an energy clash between Europe and Russia.
Gas prices have soared as Russian supplies have plunged.
Governments in Europe have been under pressure to help ease the pain of sky-high energy bills for households and businesses as winter nears.
The crisis also has raised fears of rationing and recession.
Mr Michel’s statement comes after authorities in Denmark said that the operator of Nord Stream 2 confirmed that a leak in the pipeline had been detected southeast of the Danish island Bornholm.
The pipeline runs 1,230 kilometres (764 miles) from Russia through the Baltic Sea to Germany.
“It is the authorities’ clear assessment that these are deliberate actions - not accidents,” Danish prime minister Mette Frederiksen said Tuesday.
On Monday the German economy ministry said that the Nord Stream 1 pipeline leading from Russia to Europe reported a drop in pressure.
“We are investigating this incident as well, together with the authorities concerned and the Federal Network Agency,” the ministry said in a statement late Monday.
“We currently do not know the reason for the drop in pressure.”
Seismologists have said that powerful explosions preceded the leaks. Bjorn Lund, director of the Swedish National Seismic Network told the Associated Press, that the first explosion was recorded early on Monday southeast of the Danish island of Bornholm.
A second, stronger blast northeast of the island that night was equivalent to a magnitude 2.3 earthquake. Seismic stations in Denmark, Norway, and Finland also registered the explosions.
“There’s no doubt, this is not an earthquake,” Mr Lund said.
Speaking on the leaks the Kremlin spokesperson Dmitry Peskov said: “This is an unprecedented situation that requires an urgent investigation. We are extremely worried by this news.”
(Additional reporting by agencies)