He said: "He looks happy, mate. Yeah! I haven't met Taylor personally, they only got here few days ago."
Meanwhile, Hiddleston, 35, was recently forced to deny reports that his and Swift's relationship is a publicity stunt.
He said: "That notion is, look, the truth is that Taylor Swift and I are together, and we're very happy. Thanks for asking. That's the truth. It's not a publicity stunt."
And Hiddleston previously revealed he celebrated being nominated for an Emmy by going to the screening.
He said: "I didn't have any expectations, and suddenly my phone started blowing up a couple hours ago.
"This is the most wonderful surprise, and honestly the most thrilling thing about it is that it feels like an extraordinary and heart-warming affirmation for the whole team who made The Night Manager. Making The Night Manager was the most fulfilling team effort, and I'm so proud of everybody.
"I was dozing off because of a long day as Loki. I couldn't stay awake, so I was drifting away to sleep. Earlier, Chris Hemsworth had just hosted a screening of the new Ghostbusters film, so that was a couple of hours before the nominations were announced.
"I saw that with Chris and Mark Ruffalo and Taika Waititi, who is directing Thor: Ragnarok, then came home and brushed my teeth and went to bed - and then I was nominated for an Emmy. So that was how it went."