The former couple - who were together for four years from 1994 - are both featured in the promotional clip for the music legend's new single 'Queenie Eye', and although there are still ''raw emotions'' at play neither could pass on the offer.
An insider told the Daily Mirror newspaper: ''They really try to avoid one another in public because there have been raw emotions in the past - but neither could say no to Macca.
''They only have little roles, but it's the first time they're appearing on screen together since the split.''
Kate has since got married to Jamie Hince and Johnny was dating Vanessa Paradis until last year - and the 'Hey Jude' musician was delighted to have them taking part.
He said: ''They are friends of mine and [my daughter] Stella's. I am very lucky they agreed to do it.''
However, they weren't the only stars attending the shoot at the iconic Abbey Road Studios.
The source added: ''There were a whole host of celebrities taking part. It was a really mixed bunch.
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