Ronan Keating is criticised by fans for treating his baby son to a sugary biscuit

Ronan Keating has come under fire for letting his baby son eat sugary biscuits.

The comments came after the Boyzone singer shared a shot of the toddler tucking into a Farley's Rusk on Instagram.

'Cheese !!!! It's Friday night and this boy deserves a Farley's Rusk - my childhood fav #Yum #CooperKeating,' he wrote.

Ronan accompanied his words with an adorable black and white picture of the tot flashing a winning smile while gripping his treat in one hand.

Unimpressed by the sweet snack Ronan had selected for his lad, one follower said: 'Too much sugar in these for babies. My lil one is 6months and I certainly won't be giving her rusk due to finding this out.'

Another agreed: 'I used to love them until I found out that there's 11 teaspoons of sugar in each rusk.'

Others, however, quickly jumped to Ronan's defence by arguing that he's done nothing wrong.

'My gorg girl is 7 months and loves her Farley's Rusks (bite for her bite for mummy)', one mused.

'Get a life guys much more going on in the world than a baby having a rusk 😂 Cooper Keating you handsome little boy enjoy it.'

A second admirer quipped: 'My boys used to love Rusks, I used to eat them now and then, they're not bad. You and Cooper have to try the banana ones, they're lovely.'

Ronan and his Australian wife Storm Keating, 36, welcomed Cooper in April last year.

While Cooper is fashion designer Storm's first child, the 40-year-old crooner has three other children from his marriage to Yvonne Connolly.

Ronan and Yvonne's son Jack was born in 1999 and daughters Marie and Ali followed in 2001 and 2005.