U2 frontman Bono has opened up about the moment in 2000 when he first learned that he has a half-brother.

The singer spoke about the family discovery in a new interview with BBC Radio 4’s Desert Island Discs.

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“I have another brother, whom I love and adore, who I didn’t know I had,” he told host Lauren Laverne, before explaining that his mother Iris, who died in 1974, did not know her husband had had a child with another woman.

“It’s a very close family,” Bono said. “And I could tell my father had a deep friendship with this gorgeous woman, who’s part of the family, and then they had a child. And this was all kept secret.”

After Bono found out about his half-brother, he spoke to his father about it prior to the latter’s death in 2001. “I asked him, did he love my mother, and he said yes,” Bono recalled. “And I said, ‘How could this happen?’ He said, ‘It can’, and that he was trying to put it right.

“He wasn’t apologising, he was just stating: these are the facts. And I’m at peace with it.”

Asked whether his mother knew, Bono replied: “No, nobody knew. My father was obviously going through a lot, but partly his head was elsewhere because his heart was elsewhere.”

Bono, who has another older brother called Norman, went on to describe his relationship with his father as “complicated”.

“I’m sure I was hard to deal with. And he was coping with a lot. He didn’t know quite what was going on. And I subsequently understood he was coping with other stuff.”

In November, Bono will publish his memoir Surrender: 40 Songs, One Story.