Colbert, who arrived back in the United States on Sunday night, said the excursion took many months of planning; he and his crew shot 13-hour days and filmed about four or five segments. But "You know who did know I was in Russian Federation?"
"Russian intelligence was very aware of Colbert's visit, and the host joked, "[They're] hardcore fans, evidently - followed me everywhere".
There's going to be a Russian Federation week on the Late Show in the near future where Colbert plays the segments he shot while traveling around. I could be giving state secrets to the Russians.
Colbert assured viewers on Monday that he has plenty of video from the Russian trip - at Trump's expense, no doubt - to be shown throughout the week.
A multi-talented and respected host, writer, producer, satirist and comedian, Colbert is well-known for his previous late night show, "The Colbert Report", which concluded on Friday, Dec. 18, 2014. "I'd have my son-in-law ask them", he said in jest to the roaring crowd.
He continued, "Also got some attention from American intelligence. Oh, wait. Somebody's already got that covered". The CIA reportedly captured intelligence that Russian officials were working to help Trump's campaign, but the president and the administration have vehemently denied collusion with the Russian government.
Colbert also teased Trump on Twitter, replying to the president's tweets about possible recordings of his conversations with fired FBI Director James Comey.