It won't come as a huge surprise to the band's fans as the guitarist hadn't gone on the road to take part in their recent European gigs.
"I don’t really know how to explain in a note how I could have come to a decision like this," he said in a statement.
“But please believe me when I say that this is the best thing for me in my life and also for the band.
“Please don’t be sad or angry over this and most of all, please don’t be divided about this, this is a good thing and will be good for everyone.”
He added: " I want to say thank you to Jared [Leto] and Shannon [Leto] for allowing me the privilege to be a small part of their dream and to have been able to share the stage with them for so long."

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— Uncle Tomo (@tomofromearth) 11 de junio de 2018