“Think about it, trying to co-opt the word ‘marriage’ is like trying to co-opt the word ‘love’,” he told the Irish Times.

“You can’t own it. Marriage is now an idea that transcends religion. It is owned by the people. They can decide. It is not a religious institution,” the 55 year-old said 24 hours before the tour kicks off.

“It is a hard thing to hold on to, and anything that brings that together is a totally wonderful thing,” before adding that the Church doesn’t have ownership of marriage.

“There was marriage before the Christian church. And indeed some of my favourite characters in the Bible had lots of marriages – at the same time. So, how did that work?” he laughed.

“As far as I know, Jesus wasn’t a married man and neither are most priests talking about it. It is not a religious idea.”

“It is a wonderful thing. If you believe it is just a man and a woman – great, live it! But you have to know that more than 50 per cent of the population can’t. So anyone who can is defying the odds already. So here is what I have to say about it: wherever marriage occurs, it should be encouraged.”

Bono has been married to Ali Hewson since August 1982 and they have four children.