BRUSSELS — The European Union suspects that damage to two underwater natural gas pipelines was sabotage and is warning of retaliation for any attack on Europe’s energy networks, EU foreign policy chief Josep Borrell said Wednesday.

“All available information indicates those leaks are the result of a deliberate act,” Borrell said in a statement on behalf of the 27 EU member countries. “Any deliberate disruption of European energy infrastructure is utterly unacceptable and will be met with a robust and united response.”

Seismologists reported Tuesday that explosions rattled the Baltic Sea before unusual leaks were discovered on two underwater natural gas pipelines running from Russia to Germany.

Some European leaders and experts pointed to possible sabotage given the energy standoff with Russia provoked by the war in Ukraine. The three leaks were reported on the Nord Stream 1 and 2 pipelines, which are filled with natural gas but are not delivering the fuel to Europe.

The damage means that the pipelines are unlikely to be able to carry any gas to Europe this winter even if the political will to bring them online emerged, according to analysts.

Borrell said the EU will support any investigation into the damage, and “will take further steps to increase our resilience in energy security.”

Danish Prime Minister Mette Frederiksen has said that “it is the authorities’ clear assessment that these are deliberate actions — not accidents.”

But she said “there is no information indicating who could be behind it.” Frederiksen rejected the suggestion that the incident was an attack on Denmark, saying the leaks occurred in international waters.

Denmark’s defense minister, Morten Bodskov, was meeting Wednesday with NATO Secretary General Jens Stoltenberg.