Russia's President Putin likens the Nord Stream pipelines' damage to "international terrorism."
NATO said the pipelines carrying natural-gas from Russia to Europe have been sabotaged.
A Russian foreign ministry spokeswoman said the US would benefit from the leaks.
Russian President Vladimir Putin has called the "unprecedented sabotage" to the Nord Stream natural-gas pipelines "an act of international terrorism," according to a Thursday Kremlin statement.
Putin made the comment over a phone call with Turkish President Tayyip Erdoğan, according to the readout.
Leaks to the key Nord Stream 1 and 2 pipelines transporting natural-gas from Russia to Europe were first detected on Monday in the Danish region of the Baltic Sea. More leaks have since been discovered, with Sweden on Wednesday announcing it detected a fourth leak.
The North Atlantic Treaty Organization (NATO) said in a Thursday statement, that the damage is the "result of deliberate, reckless, and irresponsible acts of sabotage." It has threatened to retaliate, stating: "Any deliberate attack against Allies' critical infrastructure would be met with a united and determined response."
The finger-pointing continues, with Kremlin spokesperson Dmitry Peskov saying the damage to Nord Stream appeared to be due to state-sponsored terrorism, Reuters reported on Thursday.
"This looks like an act of terrorism, possibly on a state level," said Peskov, according to Reuters. "It is very difficult to imagine that such an act of a terrorism could have happened without the involvement of a state of some kind."
Russia's foreign ministry spokeswoman Maria Zakharova told a pro-Kremlin online broadcast Thursday, the US would benefit from the leaks because it would be able to export more liquefied natural gas if the pipelines couldn't work, per Reuters.
The leaks had happened in areas "fully under the control of US intelligence," Zakharova told Soloviev Live, according to the news agency. "It happened in the trade and economic zones of Denmark and Sweden. There are NATO-centric countries," said Zakharova. She did not provide evidence of this claim, according to Reuters.
Denmark is a NATO member, while Sweden has applied to join the political and military alliance.
Zakharova also demanded an explanation from President Joe Biden on "whether the United States acted on its threat" to "end #Nordstream," the Russian foreign ministry tweeted on September 28.
She was referring to Biden's statement on February 7 that the Nord Stream 2 gas pipeline would be halted if Russia invades Ukraine.
White House Press Secretary Karine Jean-Pierre said at a Wednesday press briefing, that Biden was referring to how the Nord Stream 2 wouldn't commence working and rejected allegations that the US is responsible for the leaks, according to an official transcript.
"The President said that NS2 wouldn't become operational and we would work with Germany on that," said Jean-Pierre. "And he was right, because Germany took the step in February to freeze it, which was widely reported by all of you. And so that is what the President was talking about at that time."
The Nord Stream 2 has never started commercial operations because Germany shelved the project in February, days before Russia invaded Ukraine on February 24.