Speaking to HELLO! at the star-studded event at London's Royal Festival Hall, on Thursday, 24 February, Sam supported his leading lady for her choice to attend the event virtually. He said: "Cait's in America, she's just had a child and right now, with everything going on in the world, we're just glad she can be a part of it virtually."
WATCH: Outlander's Sam Heughan and Caitriona Balfe's spark sizzles off in unearthed clip
He added that although Caitríona's absence was felt at the event, the rest of the cast were more than making up for it. "We have a large contingent of a very troublesome cast so watch out tonight!"
The Irish actress was unable to join Sam and other cast members, including Richard Rankin, Sophie Skelton, and author Diana Gabaldon at the London event, but appeared on her own red carpet in LA, where she is currently with her husband Tony McGill and six-month-old son.
Caitríona tuned into the event virtually from LA
However, she came under fire from die-hard fans on Twitter not long after the news of her absence was announced earlier this week.
Taking to Twitter, she wrote: "To all those saying it's shameful I'm not there in person, I understand you're disappointed but I also ask for some understanding as a new mom. I'm trying to do the best I can and not being able to fly across the world like I used to is a change but we are adapting…."
The rest of the cast were in attendance to celebrate the joyous event
In a follow-up tweet, she added: "I'll be there virtually for red carpet and panel and it's not @Outlander_STARZ's fault … We're all trying to give you all the best experience we can in new and challenging circumstances."
Edith Bowman, who hosted a panel event with the cast of the show at the premiere event, also defended her. "You are amazing. An inspiring woman and mum xxxxx," she wrote on Twitter to which Caitríona replied: "Sorry to miss you in person @edibow but I know my peeps will take good care of you xxx."
It's believed the actress is in LA to attend the Screen Actors Guild awards ceremony on Sunday evening, where she is in the running for best supporting actress for her role in Belfast. The cast of the film has collectively received a nod for best ensemble, while Caitríona is the only star up for an individual prize.