The call starts innocently enough: Rep. Maxine Waters (D-Calif.) warmly greets the voices on the line, whom a staffer identifies as Greta Thunberg and her father, Svante. They share a laugh about Waters’s nickname, “Auntie Maxine.” The congresswoman praises her young caller for her climate change activism.

“You have made quite a big, big, big, big thunder on this issue. I am really, really very proud of you and the work that you’re doing,” Waters is heard saying.

The congresswoman and her staff thought they had connected with Thunberg, the 17-year-old Swedish climate activist who was recently named Time magazine’s “Person of the Year.” In reality, two 30-something Russians, Vladimir “Vovan” Kuznetsov and Alexei “Lexus” Stolyarov, were on the other end of the line. The duo describe themselves as comedians and pranksters, but they are widely suspected of having ties to the Russian government.

Audio from the call with Waters was posted to the pair’s YouTube page on Thursday, along with a cartoon animating the approximately 10-minute interaction as part of their comedy video series called “Stars Save the Earth.”

It’s unclear when exactly the call took place. Waters’s office did not respond to questions seeking details about how the call was arranged or whether her office has screening or security protocols for phone calls. Waters waved off the incident on Saturday, telling The Washington Post in an email statement:

“This was just another stupid prank by the same Russian operatives who have targeted many U.S. elected officials, including Rep. Adam Schiff, Sen. Lindsey Graham, Sen. Mitch McConnell, and late-Senator John McCain, and international heads of state such as Emmanuel Macron. The end.”

But security experts warn that what’s being passed off as prank-call mischief is really Russian misinformation meant to undermine the United States.

Kuznetsov and Stolyarov deny they’re Kremlin-backed agents with ties to Russian security forces, despite their pattern of frequently targeting people critical of Russia or the fact that, as two supposed pranksters, they’re able to reach powerful world leaders directly by phone.

“We work for ourselves, for nobody else,” Stolyarov told the Guardian in 2016.

Whether the pair are agents of the Russian government, the kind of ruse they pulled on Waters can accomplish two goals for Russia, according to Kathleen Hall Jamieson, a communications professor at the University of Pennsylvania and the author of the 2018 book, “Cyberwar: How Russian Hackers and Trolls Helped Elect a President.”

“The first [goal] is adding info to a political dialogue in which discrediting one side is useful to Russia,” Jamieson told The Post by phone. “The second is being able to make the argument to the rest of the world that U.S. leaders are easily duped. Putin’s interests are served when U.S. leaders are made to look foolish in the eyes of the world.”

Kuznetsov and Stolyarov started pranking their own rich and famous countrymen around 2014, before moving on to targets like Elton John, Turkish President Recep Tayyip Erdogan and, more recently, Sen. Lindsey O. Graham (R-S.C.) and Rep. Adam B. Schiff (D-Calif.). The men pose as prominent figures their targets would be keen to speak with, engage them in conversation and then post the audio to their YouTube channel.

The call to Waters includes a mix of the absurd — the Thunberg impersonator mentions a climate strike in support of “Chon-go-Chango island” — and the overtly political.

Halfway through the call, the impersonators detail a fictional exchange between President Trump and Thunberg that they claim happened when both attended the U.N. climate summit in September. In it, they tell Waters that the president made Thunberg cry when he said, “You’ll never achieve your goals like those congressional fools who accuse me,” and “I’ll tell you the truth: I really wanted to push the Ukraine president to put my competitor on trial. And he will go to trial with you, with [a bunch of] Democrats. … I would have a separate cage for all of you.”

“Oh my god, he mentioned the Ukrainian president?” Waters is heard asking.

The caller impersonating Thunberg’s father offers that they have an audio recording of Trump’s remarks to Greta that they can provide to the congresswoman.

Waters is heard assuring the callers that her colleagues are working diligently to gather facts in the impeachment case against Trump. “[I]f the public knew he talked to Greta like that, and that she will never achieve — that will go against him, too,” she said.

Waters ends the call by offering to arrange a meeting as quickly as possible, to which the callers agree.

Schiff, Waters’s congressional colleague and the ranking Democrat on the House Intelligence Committee, received a similar call from the two men in April 2017, when one posed as the speaker of Ukraine’s parliament, Andriy Parubiy, the Atlantic reported in 2018. On the call, the impersonator told Schiff they had compromising material on Trump, including nude photos of the president.

“We will try to work with the FBI to figure out, along with your staff, how we can obtain copies,” Schiff reportedly responded. A spokesman for Schiff later told the magazine that they suspected the call was “bogus” and had alerted security and law enforcement before agreeing to take it and after.

Despite those precautions, Republican opponents like Rep. Devin Nunes (Calif.) pointed to the existence of the call as evidence Democrats were being cavalier and incautious in gathering evidence against Trump for the impeachment hearing.

“The point at which this enters the dialogue and can be used for a political attack has real consequences,” Jamieson said.

Not all targets have been Democrats, but Jamieson said it matters if the “pranksters” are reaching out to people involved in an ongoing investigation. She also advised watching to see whether reports of the stories are picked up and amplified by Russian government-controlled websites like RT and Sputnik.

“At that point, this is no longer a prank; this is engaging in disinformation,” she said.

A lingering question for Jamieson — and perhaps many lawmakers’ offices — is whether voice recognition or other technology can advance to the point where it can help verify who is on the other end.

“There’s a real vulnerability when you’re talking to someone you can’t see. You wouldn’t want the president of the U.S., or someone who has the capacity to make significant leadership decisions, to be tricked by someone who isn’t who they allege they are,” Jamieson said.

Trump already fell victim to such a prank in 2018 when U.S. comedian John Melendez, a.k.a. Stuttering John of “The Howard Stern Show,” claims to have reached the president on Air Force One by pretending to be Sen. Robert Menendez (D-N.J.).

Read more: