"Even 20 years on, here he was, this old man still with a glint in his eye, still fighting for the causes close to him. It was a great, great birthday party."

In Kerr’s own words, it’s been an exciting two decades for Simple Minds but, like anything you continue to do for such a long time, there have been lulls too.

"There was a period about 10 years ago where we were running low on gas, it was a bit like getting blood out of a stone and although we obviously didn’t decide to call it a day, why in the end did we not?

"Music really is our lives – it seems like it’s what we were born to do. Why do we do it? Why does a shark swim?"

This enthusiasm for their work is the reason they have kept going, adds Kerr, whose ex-wives are the Pretenders’ Chrissie Hynde and Holby City actress Patsy Kensit.

"It’s made it possible to get through the periods that were a bit rocky," he says.

"Even John Lennon was at home baking bread for a few years when I guess he felt he wasn’t at his creative best."

He pauses, then launches spontaneously into all the reasons Simple Minds is looking forward to their Liverpool gig.

Indeed one of the reasons he turned to music was because of a certain Liverpool FC manager who used to play for his favourite team.

"It was because of a man called Kenny Dalglish who left Celtic and went to Liverpool and I thought ‘I’m gonna give up on football and do something else’, because we loved Kenny so much," he reveals.

"In the early days we loved playing at the Royal Court.

"Liverpool has such a great heritage of music and certainly when we were growing up there were a lot of Liverpool bands that were our contemporaries.

"When we were first booked for the Summer Pops I thought ‘I don’t fancy that, some tent down by the docks’, but it was great and we’ve done some of the best gigs of the latter part of our career down there.

"Why? Because the audiences really are amazing and never let us down."

SIMPLE MINDS play the Echo Arena, Liverpool, on July 21 as part of the Summer Pops.

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