Smiling as she left her modest flat near Naples, Noemi Letizia, the 18-year-old accused of being at the heart of Silvio Berlusconi’s divorce, appeared distinctly bemused.

With her parents at her side, she told The Times that she was “absolutely not” the illegitimate daughter of the Italian Prime Minister, whom she affectionately calls “Papi”. In their first joint interview since the scandal broke, the family denied yesterday they had any inappropriate connection to Mr Berlusconi — but refused to clarify how or when they began to count him as a personal friend.

The moment that Veronica Lario, Mr Berlusconi’s wife, announced their divorce with the words, “I cannot be with a man who spends time with under-age women”, Noemi became the centre of a scandal that has rocked Italy.

It began with reports that Mr Belusconi had attended the teenager’s 18th birthday party last weekend, presenting her with a gold and diamond necklace. The visit infuriated his wife, who cited her husband’s wandering eye for younger women as a reason for divorce. Criticism from all quarters followed, including the Vatican, which urged the Prime Minister to act with the sobriety more becoming of a world leader.

Noemi and her parents attempted to scotch the speculation. Speaking to The Times at their apartment in Portici, south of Naples, the family dismissed the suggestion that she could be the illegitimate child of the Prime Minister.

“No, absolutely not. That’s my dad, over there,” she said, pointing to the smartly dressed man by her side. Indeed, the focus is now shifting from the strikingly pretty aspiring starlet to her 50-year-old father, Benedetto Letizia.

The mysterious circumstances of Mr Letizia’s acquaintance with Mr Berlusconi and long, unaccounted history in local politics where no one appears to recall his presence have led the Italian press to brand this previously unknown council worker “Signor Nessuno” — Mr Nobody. Mr Berlusconi said that he attended Noemi’s party because he wanted to talk to her father about putting forward a regional councillor, Fulvio Martusciello, for the European elections in June. But Mr Martusciello said that he barely knew Mr Letizia, having met him briefly on the campaign trail nine years ago, before “losing track” of him.

In addition, Mr Berlusconi originally said that they met when Mr Letizia was a driver for Bettino Craxi, the former Prime Minister. Not so, said Mr Craxi’s son. So, how exactly does a man like this know Mr Berlusconi? “Let’s turn it around,” Mr Letizia told The Times. “How on Earth does Berlusconi know a man like me? Why don’t you ask me that?”

Responding to the duly rephrased question, he said: “We have a good relationship, a relationship of the heart,” pressing a fist to his shirt, to demonstrate his intimacy with the richest man in the country.

The family’s apartment showed little sign of housing friends of the Prime Minister. Grocers, mechanics, and hairdressers line the busy street below, to a rowdy soundtrack of Vespas, lorries, and impatient car horns.Villa Santa Chiara, the venue where Berlusconi was the surprise birthday party guest, is a kitsch, a mish-mash of fountains and neon lights by a ring road.

Mr Letizia insisted that their acquaintance was simply proof of the Prime Minister’s common touch. “Our leader is a man of the people,” he told The Times. “What is a leader if he doesn’t take a coffee with the ordinary man, speak with the butcher or the shopkeeper? Berlusconi is close to the public. Otherwise where would the votes come from?”

But does every Forza Italia voter has the privilege of the Prime Minister at their daughter’s birthday party?

Mr Letizia smiled and replied: “It is a good relationship, isn’t it? I will always carry him in my heart. I don’t understand what the problem is. In your country, does a leader not interact with his people?”

Mr Letizia is clearly not in the Prime Minister’s pay league. In 2005, he declared a modest income of ¤12,376 from the newsagent and perfume shop business run by his wife.

Neighbours of the family are puzzled. “I’ve been friends with him for years,” said Giorgi Boccia, owner of the local pizzeria, “but until last week, I never knew of any connection with Berlusconi.

“When he told me the day after, that Berlusconi had come to the party, I said, what are you talking about? I couldn’t believe it. Then he showed me the pictures in all the papers, and there it was. Quite an enigma.”

Giuseppe Fornino, the manager of VillageGlobale, the former model agency in Noemi’s street, where she is believed to have posed for her first modelling portfolio, said he was baffled.

“She is a pretty girl but one pretty girl out of many. And how many pretty girls get that kind of access to Berlusconi? You don’t just buzz the Berlusconi button on the intercom, and he responds. It doesn’t exactly work like that.”

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