Russian media showed pictures of Carlson at several spots around Moscow, including at a box at the Bolshoi Theatre and eating at a hotel.

"It is beautiful," Carlson said of Moscow in an interview aired by the Izvestia newspaper. "I just wanted to see it because, you know, I have read so much about it but I have never seen it before."

When asked if he was in Moscow to interview Putin, Carlson said: "We'll see". He then smiled.

The Kremlin, asked the same question, said it could hardly be expected to comment on the comings and goings of foreign journalists or provide a running commentary on them.

"Many foreign journalists come to Russia every day, many continue to work here, and we welcome this," Kremlin spokesman Dmitry Peskov said. "We have nothing to announce in terms of the president's interviews to foreign media."

Carlson launched a new subscription-based streaming video service in December to capitalize on his popularity among conservative U.S. voters. An interview he posted on X with former president Donald Trump last August has drawn more than 267 million views, according to the social media platform.

(Reporting by Reuters; editing by Guy Faulconbridge, Mark Trevelyan, Philippa Fletcher)