The Russian position is also reverberating on social media forums popular with American conservatives and far-right groups.

NATO leaders believe the damage to the Nord Stream 1 and 2 pipelines between Russia and Germany is the result of sabotage. NATO has refrained from identifying a suspect pending an investigation into the damage.

Russia began blaming the U.S. quickly after the damage was reported Monday night. On Friday, speaking at a ceremony to annex four Ukrainian regions, Russian President Vladimir Putin said “Anglo-Saxons” in the West were behind the “terror attacks” but did not specify any nations.

Pravda and other Russian state outlets reported Thursday that the U.S. operates underwater robots capable of carrying out the acts of sabotage. The Russian Foreign Ministry spokeswoman wrote about her suspicions of U.S. involvement in a Telegram post.

“Europe must know the truth!” Maria Zakharova wrote on Telegram Wednesday.

President Joe Biden on Friday dismissed Russia’s claims.

“It was a deliberate act of sabotage. And now the Russians are pumping out disinformation and lies,” Biden said. “… When things calm down, we’re going to send the divers down to find out exactly what happened. We don’t know that yet exactly. But just don’t listen to what Putin’s saying. What he’s saying we know is not true.”

The assertions of U.S. responsibility cite Biden’s threat in February to stop the recently completed Nord Stream 2 pipeline if Russia invaded Ukraine. “If Russia invades … then there will be no longer a Nord Stream 2,” Biden said. “We will bring an end to it.”

The two Nord Stream lines were not in operation but were filled with tons of methane that began bubbling to the surface following the damage. Russia recently shut off the Nord Stream 1 pipeline as it ramped up energy pressure on Europe. Nord Stream 2 has never been used.

Fox News’ Tucker Carlson played the Biden clip on his show Tuesday and brought up the possibility that the U.S. was behind the sabotage.

“If they did this, this will be one of the craziest, most destructive things any American administration has ever done, but it would also be totally consistent with what they do,” Carlson said.

Former President Donald Trump also reposted Biden’s remarks on Truth Social along with a call for the U.S. to remain “cool, calm” in its relations with Russia. “Wow. What a statement. World War III anyone?” he wrote.

Contacted for a response, a spokeswoman for Fox News forwarded transcripts from past episodes of Carlson’s show, including one in which he discussed a conspiracy theory about supposed secret bioweapon research in Ukraine.

A spokeswoman for Trump did not immediately respond to a message on Friday.

The suggestion that the U.S. caused the damage was circulating on online forums popular with American conservatives and followers of QAnon, a conspiracy theory movement which asserts that Trump is fighting a battle against a Satanic child-trafficking sect that controls world events.

The claim’s popularity among the American far-right and the speed with which it spread from Russian state media reflect mounting skepticism about America’s role in the war in Ukraine, according to Emma Ashford, a senior fellow at the Washington, D.C.-based Stimson Center and an expert on security and energy.

“Russia is quite good at capitalizing on these divides, but it doesn’t create them,” she said.

It’s not the first time Russia has spread disinformation seeking to redirect blame for the war and undermine Ukraine’s allies. Earlier this year, Kremlin-controlled media mounted a disinformation operation asserting the U.S. had been running secret bioweapon labs in Ukraine. Carlson helped amplify that theory too.

Networks allied with the Kremlin have also spread frightening tales about Ukrainian refugees, and blamed atrocities committed during the war on Ukrainians.

Seen in that context, the conspiracy theory alleging U.S. responsibility for the pipeline damage is consistent, the researchers concluded.

“The central theme is that this is a “false-flag” operation, an American plot designed to convince Europe that it was a Russian attack intended to signal the vulnerability of Europe’s energy supplies,” the researchers wrote.