Silvio Berlusconi’s children rushed to his defence yesterday as the Italian Prime Minister became mired deeper in the scandal surrounding his friendship with an 18-year-old aspiring model who calls him “Papi”.

Private polls are said to show that his normally sky-high approval ratings are being hit by his failure to explain his friendship with Noemi Letizia. As he prepared to mount a television campaign to boost his flagging popularity, Mr Berlusconi appeared stung by an opposition leader questioning his family values.

Dario Franceschini, the leader of the Democratic Party, said: “To the Italians, I want to ask a question: would you want your children brought up by this man?”

Marina Berlusconi, the Prime Minister’s oldest child and an executive in his media empire, retorted: “I would be thrilled for Franceschini’s children if they had a father like mine.”

Barbara, Eleonora and Luigi — the children from Mr Berlusconi’s second marriage — also stood by their father. “We were brought up in a sensible family environment rich in values,” they said. Mr Berlusconi, 72, has confirmed that Ms Letizia stayed at his villa in Sardinia and attended a new year party there. Her former boyfriend said that Ms Letizia had told him she was one of up to 30 girls invited to the villa over the holiday.

Ms Letizia also attended a dinner he gave in Rome last year for leading businessmen, where she sat at his table, and a Christmas party he hosted in December for AC Milan, the football team he owns.

His gift of a €6,000 (£5,200) necklace on her 18th birthday at a party he attended caused his wife, Veronica, to announce that she would divorce him because she could “not stay with a man who frequents minors”. The saga appears to be taking its toll on Mr Berlusconi, who reportedly told close associates that he would not be hounded out of office by a “campaign of hate launched by the Left”.

To try to claw back the initiative before next month’s European elections, the Prime Minister is booked for a series of chat shows next week and will appear in adverts claiming that he solved the Naples rubbish crisis, saved the Alitalia airline from bankruptcy and protected Italians from the global financial slump.

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