He was seen mingling with a host of celebrities and British Royals on Saturday, when he attended Prince Harry and Meghan Markle's high-profile wedding.
But James Corden, who was seen making his way into Windsor Castle's St. George's Chapel with wife Julia Carey by his side, has revealed that he almost interrupted the extravagant nuptials at a key point in the ceremony, thanks to his pesky allergies.
Speaking on his return to The Late Late Show in Los Angeles on Monday night, the 39-year-old comedian explained that while he found the newly minted Duke and Duchess of Sussex's wedding 'beautiful', his need to sneeze became a grave worry, according to the Daily Mail.
"I get quite bad allergies if I'm in close proximity to flowers so for a lot of the ceremony I just needed to sneeze."
He then reenacted his attempts to suppress his sneezes as he sat in the church among the likes of David and Victoria Beckham and Sir Elton John.
He recalled: "Right at the point when the Archbishop was saying, 'If anyone knows of any reason that these two should not be married...' I was thinking, 'Please don't sneeze and I had to do one of those internal sneezes.
"I think I got away with it," the Buckinghamshire-raised TV personality said, after demonstrating how he kept his sneeze from being audible to attendees.
James, who has known Harry for seven years and served as a compere at the newlyweds' wedding reception, went on to gush about the ceremony: 'It was gorgeous the whole affair, it was happy, it was joyous, it was uplifting.
"It was Britain at it's finest, a picture perfect day, Windsor Castle, six hundred guests, 30,000 flowers or as Elton John calls it, a Thursday. He was there, he performed some songs in the afternoon which was wonderful."
During his recap on the proceedings, James also jokingly took a jab at Hollywood actor and Nespresso ambassador George Clooney, who attended the star-studded celebrations with his glamorous lawyer wife, Amal.
He said: "George Clooney was there so congratulations Meghan and Harry on your brand new Nespresso machine, I imagine that's what he got him."