Saudi Arabia's royals are yet to make an offer for the lavish Sardinian estate owned by Former Italian Prime Minister Silvio Berlusconi, sources said.

Berlusconi has given a tour of the luxury estate to Saudi Arabia's crown prince, a source said on Tuesday.

Prince Mohammed bin Nayef looked around Villa Certosa last week, where Berlusconi used to entertain world leaders.

The estate sprawls over 120 hectares (296 acres) on Sardinia's exclusive Emerald Coast and comes complete with a fake volcano that erupts on command. It also has an amphitheatre and an underground grotto where small boats can dock.

The crown prince "toured the villa, but that's it so far. There have been no further steps forward," the source said.

Italian daily Corriere della Sera reported last week that Berlusconi was seeking 500 million euros ($552 million) for the Mediterranean estate, which came to symbolise his flamboyant lifestyle during his years in power.

Russian President Vladimir Putin visited and his two teenage daughters were reported to have spent the summer there in 2002.

Former British Prime Minister Tony Blair once vacationed there with his wife Cherie.

Corriere della Sera said that although Saudi Arabia's crown prince had seen the property, it may be King Salman who is really interested in buying the villa.

The Saudi king earlier this month abruptly ended a planned three-week stay in the French Riviera following a petition from some 150,000 residents who were angered by the closure of a public beach outside his villa.

Berlusconi, whose political fortunes have faded in recent years, has been said to be on the verge of selling the villa many times in recent years, including to Spanish, Russian and Chinese investors.

The former leader announced this month that he was selling 48 per cent of his AC Milan football club to a group led by Thai businessman Bee Taechaubol.  - Reuters