Tucker Carlson Tonight was the most viewed cable news show in America before it was taken off-air amid a defamation lawsuit in April 2023.
The presenter has since taken his show to Twitter, where his interviews with figures such as Victor Orban, the prime minister of Hungary, and controversial online influencer Andrew Tate have reached millions of views.
Rumours of a link-up with Russia first circulated in the summer, when Russian state television ran ads with a montage of Carlson repeatedly saying “Russia” and promising: “The high-profile American presenter is moving to another level. Here.”
Carlson is popular with Russian state-controlled media. Vladimir Solovyov, an anchor on the Russia 1 channel, urged Carlson to “come join us” after Carlson’s departure from Fox News.
Dmitry Peskov, the press secretary to Vladimir Putin, said in September that he believes that the “time will come” for an interview by Western media of the Russian president, adding that “whether Carlson will be among those who will be considered for an interview, well, let’s wait and see”.
Commenting on reports of a possible meeting, Bill Kristol, former chief of staff to the vice president of the United States during the Reagan administration, suggested a temporary ban on Carslon reentering the US.
Calls to stop Carlson reentering US
Mr Kristol said: “Perhaps we need a total and complete shutdown of Tucker Carlson re-entering the United States until our country’s representatives can figure out what is going on.”
Kristol also compared Carlson’s visit to Moscow with Jane Fonda’s trip to North Vietnam during the Vietnam War, when the American actress was filmed posing on a North Vietnamese anti-aircraft gun as US troops were battling communist forces in the country.
Bill Browder, the British financier and arch-critic of Vladimir Putin, said: “As Russia conducts a genocidal war to eliminate Ukrainians and Putin is wanted for crimes against humanity by the ICC, Tucker Carlson, an American citizen and influencer, is in Moscow?!? Either he’s remarkably stupid or consciously evil. No other excuse.”
Some Republican responses have been supportive of Carlson’s visit to Moscow.
Marjorie Taylor Greene, a member of the US House of Representatives from Georgia, wrote on social media that “Democrats and their propagandists in the media are spasming at the prospect of Tucker Carlson interviewing Putin”.
In January, Donald Trump Jr, the eldest son of former US president Donald Trump, said Mr Carlson was “a contender” to be his father’s running mate in the US 2024 presidential election.
“I mean they’re very friendly, I think they agree on virtually all of these things. They certainly agree on stopping the never-ending wars. And so, I would love to see that happen. That would certainly be a contender,” Trump Jr said in an interview with Newsmax.
According to Russian Telegram channel Mash, Mr Carlson was pictured at the Bolshoi Theatre after spending three days in Moscow.
He was earlier pictured during a layover at Istanbul Airport en route to the Russian capital.
The Telegraph has contacted Tucker Carlson for comment.