When asked by a fan if Tori was telling the truth, Priestley took to Twitter.
"I'm not getting into this... It's nobody's business... Either way," he responded.
"I'm only speaking with negativity about the Lifetime movie and Tori's lie detector... Nothing but love for 90210," he added, when someone else asked why he was dissing the show on social media.
"I'm actually feeling a little nostalgic today... That show was quite an experience... I owe it a lot," he also added, as the show celebrated its 25th anniversary on Sunday.
He also revealed that, despite the cast kicking Shannen Doherty off the show, the two are close now.
"Shannen and I will always be friends... Been through too much together," he revealed.
And speaking of Shannen, she wasn't too thrilled with Lifetime's film either -- tweeting out, "'Unauthorized' is the same as following someone who pretends to be someone else. In other words, bulls**t."
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