A SAUDI PRINCE has "severed ties" with Forbes magazine saying it has undervalued his wealth by $9.6 billion in its annual rich list. As result, he is rated only the world's 26th richest man when in his view he should be 10th. Prince Alwaleed bin Talal, whose investment interests include Twitter, News Corp and London's Savoy Hotel, disputed the list after Forbes put his net wealth at $20 billion. Alwaleed estimates it is $29.6 billion. See The Business for The Week’s daily news round-up, He blasted the publication's "flawed" valuation methods, saying they "seemed designed to disadvantage Middle Eastern investors and institutions", the Financial Times notes.A statement from the tycoon's Kingdom Holding Company said he would longer cooperate with Forbes but would continue to work with those compiling the rival rich list - the Bloomberg Billionaires index, which ranks him as the world's 16th richest man. Alwaleed's placement isn't the only eyebrow-raiser on this year's Forbes list. Warren Buffett, the so-called 'Sage of Omaha', has dropped out of the top three for the first time in 13 years. The billionaire American investor, estimated to be worth $55.5 billion by Forbes, has been overtaken by Zara fashion chain founder Amancio Ortega, the richest man in Europe. Mexican business magnate Carlos Slim topped the list for the fourth time in a row with an estimated worth of $73 billion, followed by Bill Gates with $67 billion. The average age of the ten richest individuals was 74. According to Forbes, the dollar billionaires club welcomed 210 new members in the past year, taking the number up to a record 1,426. The top ten: 1. Carlos Slim $73bn, 2. Bill Gates, $67bn, 3. Amancio Ortega, $57bn, 4. Warren Buffett, $55.5bn, 5. Larry Ellison, $43bn, 6. Charles Koch, $34bn and David Koch, $34bn (joint entry), 8. Li Ka-shing, $31bn, 9. Liliane Bettencourt and family, $30bn, 10. Bernard Arnault and family, $29bn.Source: The Week UK