The former Take That star, currently at No 1 with comeback single Candy, was asked his opinion on The Voice coach Jessie during an interview on Dutch TV.
And according to The Sun, he replied: "She's not gonna last for very long, though, is she? She's great, Jessie. I give her 18 months."
Whether Robbie was being flippant or serious - or a bit of both - is unclear. But he didn't have many kind words for The Voice either.
He continued: "I don't watch it. Sometimes it's very difficult to go on the 'emotional journey with the contestants'.
"I'm exhausted with how many times I'm to go on the emotional journey with this person who had a hard luck story and then da, da, da, da, blah, blah.
"I'm sure I'd be a good judge but no, I've got a career. So..."
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