Russian President Vladimir Putin accused the US of “sabotaging” the Nord Stream pipeline and suggested that the recent attacks had been carried out to destroy Europe's energy infrastructure.
Mr Putin said that the attacks on the crucial trans-Baltic pipeline were the work of “Anglo-Saxons” during a long-winded speech announcing the annexation of four Ukrainian regions.
“The sanctions were not enough for the Anglo-Saxons: they moved on to sabotage,” Mr Putin said. “It is hard to believe, but it is a fact that they organised the blasts on the Nord Stream international gas pipelines.
“They began to destroy the pan-European energy infrastructure.”
He added that it was “clear to everyone who benefits from this”.
Russia on Friday claimed to have intelligence suggesting western involvement in the pipeline disruption, as it stepped up efforts to deflect suspicion away from Moscow.
Swedish authorities said the blasts that caused several leaks on the crucial pipeline were equal to several hundred kilograms of TNT. The country says it does not believe anyone other than a state could have caused the undersea blasts.
“The magnitude of the explosions was measured at 2.3 and 2.1 on the Richter scale, respectively, probably corresponding to an explosive load of several hundred kilos,” Sweden and Denmark said in a joint report to the UN Security Council.
Following a request from Russia, the Security Council is due to hold an emergency meeting on the leaks later on Friday.
“All available information indicates that those explosions are the result of a deliberate act,” the countries said.
All the leaks, which were discovered on Monday, are in the Baltic Sea off the Danish island of Bornholm.
Two of the leaks are located in the Swedish exclusive economic zone and the two others in the Danish one.
The Scandinavian countries also said that “the possible impact on maritime life in the Baltic Sea is of concern, and the climate effect would likely be very substantial”.
Coastguards widened the maritime exclusion zone as gas escaped the pipelines for a fifth day, although there were signs at least one of the leaks was diminishing.
Denmark said the methane leaking from the pipes could be equivalent to a third of its annual greenhouse gas emissions.
There were 778 million cubic metres of gas in the pipes even though none was being exported, Danish authorities said. Both the parallel Nord Stream 1 and Nord Stream 2 pipelines have two leaks.
Amid suspicion that Russia was behind the leaks, the head of its foreign intelligence service, Sergey Naryshkin, said Moscow had clues “that point to the western footprint in the organisation and implementation” of the blasts.
“The West is doing everything to hide the true perpetrators and organisers of this international terrorist act,” news agency Interfax quoted the spy chief as saying.
Kremlin propaganda highlighted American opposition to the Nord Stream 2 pipeline and a remark by US President Joe Biden in February that, if necessary, “we will bring an end to it”.
The US has dismissed suggestions it was involved as Russian disinformation.
“We're as perplexed as anyone else and are very interested in knowing how this came about, whether it's an accident or otherwise,” a senior Pentagon official said this week.
Suspicion has fallen on Russia because of the backdrop of its energy stand-off with Europe, its record of shadowy operations and the suggestion that it wants to unsettle western powers about the safety of their vital infrastructure.
Sweden, one of the countries with gas leaking in its exclusive waters, said on Friday that the leaks “should be seen from the current security situation that Europe is in”.
“It’s very likely that it has been done deliberately and not by accident, and it’s very unlikely it’s been done by anybody else than a state without being detected earlier,” Energy Minister Khashayar Farmanbar said.
Nato said on Thursday it regarded the leaks as sabotage and gave a warning that any deliberate attack against allied infrastructure “would be met with a united and determined response”.
An update from Swedish coast guards on Friday said the leak on Nord Stream 2, the smaller of the two in Sweden’s waters, “has diminished, but is still ongoing”.
As of Thursday evening, passing ships were being told to stay at least seven nautical miles (13 kilometres) from the source of the leak, increased from five.
The rescue ship KBV 03 Amfitrite, built to withstand contaminated environments, was patrolling the leak around the clock amid security concerns around Europe.
French company TotalEnergies added to those concerns late on Thursday by saying it had spotted unauthorised drone activity near one of its North Sea oil and gas installations.
Norway similarly reported drone sightings as it announced it would increase security on its continental shelf following the leaks.
Seismographs in Germany, Denmark and Sweden recorded two separate spikes in the Baltic Sea shortly before the leaks were discovered, in what appeared to be man-made blasts rather than earthquakes.
The mainly Russian owners of the two pipelines told Danish authorities that there were 600 million cubic metres of gas in Nord Stream 1 and 178 million in Nord Stream 2 at the time of the blasts.
Although some of the gas may dissolve in the air and water, the worst-case scenario calculated by Danish scientists suggests the equivalent of 14.6 million tonnes of CO2 would leak into the atmosphere.
This would be equivalent to 32 per cent of Denmark’s annual greenhouse gas emissions, the country’s energy agency said.