Credit:The Dolly Mama(Flickr)

More than 20 cases have been reported of new mothers being given wrong babies to breastfeed in the past three years.

New South Wales Premier Kristina Keneally commented that such mix-ups at public hospitals are totally unacceptable.

Ms Keneally says new rules have been implemented making it mandatory for babies to be kept with their mothers in their rooms unless there is a good clinical reason preventing it.

She says she empathises with those who have been victims of mistakes in the past.

It is unacceptable, absolutely unacceptable. And this is why in March this year NSW health put in place new procedures that seek to prevent this from happening, she said.

The Health Department's Dr Michael Nichol says there have been no known instances of it happening since the new rules were put in place.