As Wills and Kate arrived, the Sussexes watched on as they chatted to Harry’s uncle Prince Edward and Sophie, Countess of Wessex, who were seated next to them.
William then appears to acknowledge his brother and sister-in-law, as he looks across the chairs in their direction, however, Kate’s gaze is brief as she turns around and sits down.
Royal fans were quick to take to Twitter to comment on the icy meet and greet, with one person writing: “I’m still chipping the ice off my phone screen! Ouch!”
They added: “Definitely a chill between the Cambridge’s and Sussexes! Megan attempted to say hello 3 times to no avail. Harry does NOT look happy at all.”
Another person stated: “Can't blame Kate for snubbing the troublemaker! Not only has Meghan taken over thinking for Harry, but she also caused all kinds of pain for the rest of the family!”
A third person added: “It looks as though William looks over… Catherine doesn't. They may be Royal, but they're human. Looks like a lot of hurt feelings.”
The awkward interaction at the annual Commonwealth Service, which took place on Monday, marks Harry and Meghan’s last official engagement as senior royals.
Harry and Meghan are due to step down on March 31, and Monday’s outing was the first time they saw William and Kate since they stepped out together for Remembrance Day events in November.