The 'Read All About It' hitmaker hit it off with the Coldplay frontman when he supported the British band on tour and Green revealed Chris had been particularly empathetic when he heard the rapper's father had committed suicide.
He explained to The Sun newspaper: "Chris is clearly a brilliant mind. He took us out to dinner when we were on tour with their band and I really enjoyed having a good chinwag with him.
"He's very inquisitive. We went for dinner and he was asking me questions about growing up.
"Somehow we got on to the subject of my dad and obviously, with him having committed suicide, it all got quite dark. But instead of switching subjects we ended up talking more.
"It resulted in him saying, 'Well, if ever you are thinking about committing suicide, just phone me and we'll go for a pizza and just talk'."
"He is very, very typically English - very polite and he seems to care about the right things."
However, Professor Green doesn't reserve his praise for just Chris, he says Coldplay and their entire entourage were extremely welcoming to him.
He said: "Everyone in their crew took the time out to say 'Hi' and have a conversation with us. A lot of people don't take the time to do quite a lot of things as soon as they get any sniff of success, but it's the total opposite with Coldplay."
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