CIA Director Mike Pompeo recently met with his Russian counterparts when they traveled to the US, according to US ambassador to Russia Jon Huntsman.
Russian media is reporting those who met with Pompeo may have included the country's sanctioned spy chief, Sergey Naryshkin.
Talks between top US and Russian intelligence officials occurred just days before Pompeo once again warned that Russia will attempt to meddle in the 2018 US midterm elections and the Trump administration released a sweeping list of prominent Russian political and business figures in defiance of Moscow.
While neither US nor Russian officials explicitly said that Pompeo and Naryshkin met, both sides confirmed that talks occurred between intelligence counterparts and Antonov said that Naryshkin made a trip to the US for discussions.
Speaking on the Russia 1 TV channel, Antonov said that even during the "hardest times," contacts between the special services have continued.
"Politics is politics, work is work. There are political proclamations, there is real work," he said. "You probably remember that Vladimir Vladimirovich [Putin] called Donald Trump and thanked him for help, for the information that was received through the line with the CIA, and thanks to that [we] were able to prevent a horrible act of terrorism in St Petersburg."
Naryshkin was sanctioned in 2014 by the Obama administration in response to Russia's actions in Ukraine, and his meeting with Pompeo came just days before he was named in a report released by the US Treasury Department dubbed the "Putin list."
"I think this conversation was necessary and very useful. I am sure of it. And of course I'm not going to deceive you -- Sergey Evgenyevich [Naryshkin] was here. He came. He held consultations with his colleagues," Antonov said.
Huntsman also said in an interview with the Echo Moscow radio station on Tuesday that Pompeo met with Russian intelligence officials last week, but he did not specifically name Naryshkin.
Timothy Barrett -- a spokesman for the Office of the Director of National Intelligence -- responded to CNN's request for comment with the following statement: "While we do not discuss the schedules of US intelligence leaders, rest assured that any interaction with foreign intelligence agencies would have been conducted in accordance with US law and in consultation with appropriate departments and agencies."
Both US and Russian officials indicated that the discussions had centered on cooperative efforts to combat terrorism, but Senate Minority Leader Chuck Schumer is demanding to know the details.
"The Trump administration must immediately come clean and answer questions," the New York Democrat said about Naryshkin's visit. "Which US officials did he meet with? Did any White House or National Security Council official meet with Naryshkin? What did they discuss?"
News of the talks surfaced as Pompeo warned -- once again -- on Monday that Russia will attempt to interfere in the 2018 US midterm elections.
For months, Pompeo has highlighted Russia's efforts to influence the 2016 presidential campaign -- despite the unwavering skepticism of Trump -- and raised concerns that it will target the November midterms.
"I have every expectation that they will continue to try and do that, but I'm confident that America will be able to have a free and fair election [and] that we will push back in a way that is sufficiently robust that the impact they have on our election won't be great," Pompeo told the BBC.
Asked if he must "walk a fine line" due to Trump's dismissive attitude about claims of Russian election interference, Pompeo said: "I don't do fine lines. I do the truth."
"We deliver nearly every day personally to the President the most exquisite truth that we know from the CIA," he added.
Those remarks echo what Pompeo said in October when he indicated that outside interference remains a threat to the midterm elections and the next presidential election, in 2020.
"We are at risk in 2018 and 2020 ... we are always at risk," he said.
But despite repeated warnings and reassurances that the CIA -- along with the entire Trump administration -- is working to counter Russian meddling efforts in upcoming elections, Pompeo has offered few specifics as to what steps will be taken.
And lawmakers on both sides of the aisle have warned that the time for action is now.
Sen. Ben Cardin of Maryland, the senior Democrat on the Foreign Relations Committee, released a new report this month concluding that the US will not be prepared to defend against possible Russian meddling unless it takes immediate action.
Pompeo's latest comments come on the heels of a US Treasury report that the administration is framing as a first step in its plan to punish Russia for election meddling.
The report, published shortly before a midnight deadline on Monday, listed every senior member of the political administration at the Kremlin, and every Russian oligarch with a net worth of $1 billion or more.
Some of those named are already subject to US sanctions. But the administration stopped short of imposing any new punishments, saying the legislation was already doing its job. The report was "not a sanctions list," it said.
Instead, the Treasury report resembled an exercise in naming and shaming -- putting individuals on notice that they may be subject to sanctions in the future.
On Tuesday, Treasury Secretary Steven Mnuchin disputed claims that the Trump administration had punted on moving forward with fresh sanctions against Russia over its interference in the 2016 US election.
Appearing before the Senate Banking Committee, Mnuchin assured lawmakers that additional sanctions would be imposed in the "near future."