The Beady Eye frontman allegedly left Michael's London concert after 23 minutes to stand at the bar with his bandmate Andy Bell.
"Please don't hold it against Liam that he popped off to the bar at Saturday's show", Michael tweeted, defending the star's decision.
"He's a lovely guy and has always been really friendly to me and very complimentary about my music."
He added: "He was getting a load hassle from people who spotted him so it's not surprising he went for for a bevvy. You know what the tabloids are like,they love love to have a go at him."
Michael's tweets were re-tweeted by former All Saints star and Liam Gallagher's wife Nicole Appleton, who was also at the gig at Earls Court on Saturday evening.
George Michael recently admitted that he no longer makes long-term plans after coming close to death last year.
Watch the music video for George Michael's recent single 'White Light' below: