“WHEN you speak,” shouts a ten-year-old boy in the audience, “the birds stop twittering so that they can listen to you. I present my feelings to you in a bouquet of flowers.”

The flowery tribute is a precursor to an appeal by the boy who has come to the Saudi Arabian desert to plead for benevolence from the world’s sixth richest man. Prince Alwaleed bin Talal bin AbdulAziz Alsaud sits in a vast tent on a cool winter’s night 60km from Riyadh and ponders how to hand out the proceeds from his estimated $20 billion (£13 billion) fortune.

Although surrounded by 500 Beduin tribesmen in traditional robes and singing his praise, the prince is distracted by the many television sets that dot his desert camp. It has not been a good year for his portfolio of investments and his attention wanders to the business data on the screens.

Stakes in companies such as Citigroup, AOL Time Warner, Motorola, Apple Computer and Euro Disney have buckled under the weight of falling global sentiment in equity markets. In recent weeks, he says, gains in some share prices have lifted his handful of long-term investments to about breakeven over the past year.

Besides monitoring his key holdings, he also makes constant adjustments to a $1 billion trading portfolio, which provides much of the funds that supports his lifestyle and philanthropic pursuits.

Every week he goes to his desert camp to receive petitions from needy Saudis, whose requests range from money for expensive surgery to repaying personal debts. All are granted a moment to kiss the prince’s shoulder, the traditional greeting of royalty, and to present their case.

One man says he has 12 children to feed and needs help to repay debts of $40,000, while another needs to pay for heart surgery after two bypass operations. He reveals the scars on his chest to prove it. The petition is added to the pile.

Many visitors, such as the boy, try to charm the prince with poetic tributes. Others simply hand over a letter. Very few petitions that get this far are rejected. A night such as this can cost the prince up to half a million dollars.

As if to remind the petitioners of where the money comes from, the prince sits with his back to a wall plastered with global brand names, each of them owned by a company in which he holds shares. A man petitioning to have his mobile phone bill paid might glance over the prince’s shoulder to see Motorola’s distinctive M.

The prince, 47, donates more than $100 million a year to various causes. Previous donations have included funding new bridges and roads, to the distribution of power stations in remote parts of Saudi Arabia and providing sewing machines to Moroccan widows. But in the political minefield of the Middle East, large donations can attract controversy. This year the prince gave £18 million towards repairing parts of the Palestinian territory destroyed by Israeli tanks.

This contribution, however, led to a suggestion that the money went to families of suicide bombers, an accusation strongly denied by a member of the prince’s staff.

The prince also failed to see eye-to-eye with Rudolph Giuliani, New York’s Mayor at the time, after the devastating terrorist attack on the World Trade Centre last year. Mr Giuliani returned the prince’s donation of $10 million after he urged the United States to re-examine its political approach to the Middle East and adopt a more balanced stance towards the Palestinians.

The prince’s immense wealth allows him to enjoy life’s luxuries: he owns a $100 million palace in Riyadh, the Saudi capital, and a 282ft yacht once owned by Adnan Khashoggi and Donald Trump. But being a rich Arab, in fact, the richest, has imbued him with a sense of responsibility.

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