The 'Love Me Again' hitmaker - who collaborated with the Scottish DJ on the hit single 'Blame' - has revealed the first time the pair met was at a supermarket where Calvin was popping in to buy some sweet treats.
Asked how he got to collaborate with him, John said: ''I met him when he was going to Tesco to buy flapjacks and a bird had s**t on his car and from there we became mates and made this tune together.
'''Blame' was the first idea that I had and it was amazing.
''I remember touring at the time and sending the track back and forth.''
John told The Sun newspaper: ''We are both very honest people, him being from Scotland and me from Yorkshire and we don't hid our opinions about things.
''When I was making the record out in America he was the guy who was giving me honest feedback about the record, what worked and what didn't work.
''It was really good to have him there because despite all of that s**t that gets thrown up around him, the guy is really very humble and a just lovely, genuine person.''
John's new album 'Revolve' is out now.
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