The Britain's Got Talent judge, who worked alongside Piers on the talent show during the first four series, shared a throwback snap of herself and Piers enjoying a glass of wine together on Instagram.
WATCH: Susanna Reid reacts to Piers Morgan's GMB exit
Responding to his shock news, Amanda said: "We've both been described as #marmite in our time. I don't always share the same opinions as him but my goodness he's a good and loyal friend #alwaysthereforeachother."
Upon seeing her post, Piers shared the Story and added a heart emoji. The outspoken broadcaster, 55, abruptly quit GMB on Tuesday night following his comments regarding Meghan Markle and her interview with Oprah Winfrey.
He ended his six-year tenure on GMB with immediate effect. ITV confirmed in a statement: "Following discussions with ITV, Piers Morgan has decided now is the time to leave Good Morning Britain. ITV has accepted this decision and has nothing further to add."
Amanda Holden shared this sweet throwback
It was later revealed that Meghan herself had formally complained to the broadcaster about Piers' comments. According to PA, Meghan's concern was not about the personal attacks on the validity of her racism allegation made against the royal family, nor her claims she was not supported by the institution when experiencing suicidal thoughts.
Instead, the complaint is understood to focus on how Piers' comments may affect the issue of mental health generally and those attempting to deal with their own problems.
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