Kate Middleton called “plastic princess” as she shows off her baby bump

Kate Middleton stepped out for her first public engagement in months as outrage continued over controversial comments by author Hilary Mantel that the Duchess of Cambridge is "plastic" with "dead eyes". 

Middleton, 31, appeared at Hope House in South London Tuesday wearing a grey wrap dress that showed a slight hint of a baby bump, ABC News reported. 

Her official appearance follows the unauthorised publication in gossip magazines last week of photos of the Duchess in a bikini on a private family holiday in the Caribbean. 

It also came a day after Mantel, a Booker Prize winning author, made scathing remarks about Middleton during a lecture, International Business Times reported.

Speaking at a lecture for the London Review of Books, Mantel said: "I saw Kate becoming a jointed doll on which certain rags are hung. In those days she was a shop-window mannequin, with no personality of her own, entirely defined by what she wore.

"These days she is a mother-to-be, and draped in another set of threadbare attributions. Once she gets over being sick, the press will find that she is radiant. They will find that this young woman's life until now was nothing, her only point and purpose being to give birth." 

The British Prime Minister David Cameron leapt to Middleton's defence and told the BBC: "I think (Mantel) writes great books, but I think what she's said about Kate Middleton is completely misguided and completely wrong."

"What I've seen of Princess Kate at public events, at the Olympics and elsewhere is this is someone who's bright, who's engaging, who's a fantastic ambassador for Britain.

"We should be proud of that, rather than make these rather misguided remarks."