Image caption Prince Alwaleed has claimed there were inconsistencies in the magazine's valuation process

Saudi Arabia's Prince Alwaleed Bin Talal has accused Forbes magazine of understating his wealth.

In its 2013 list of the world's richest people, Forbes estimated Prince Alwaleed's net worth at $20bn (£13bn), putting him in 26th place.

According to reports, the prince estimates his net worth to be $29.6bn, which would put him in the top 10.

Forbes said it had examined the prince's wealth "deeply" following claims he had exaggerated his fortune.

In an article published on its website, Forbes also said that the prince often went to great lengths to affect his ranking and had complained in previous years about the valuation Forbes had put on his wealth.

"Of the 1,426 billionaires on our list, not one - not even the vainglorious Donald Trump - goes to greater measure to try to affect his or her ranking," the magazine claimed.

Citing former associates of Prince Alwaleed, the magazine said his ranking was very important to the prince.

"This is how he wants the world to judge his success or his stature," an anonymous source was quoted as saying.

Analysis A journalist who used to work on the Sunday Times' annual UK Rich List says: Conventional wisdom says that the wealthy only discuss their riches with the bank manager and the tax inspector. But when I helped compile the Sunday Times' annual UK Rich List there were always people keen to flaunt their millionaire status. Not the super rich, for whom counting the pennies was pointless as they probably had no idea of their actual value. But for the nouveau millionaire a slot in the Rich List was a badge of honour. The calls would start coming in a few weeks before publication, never from the people themselves, but from a PR minion or marketing person. Had we got all the information we needed? Were we aware of this or that deal? Entrepreneurs, celebrities, wannabes: there was always someone angling for official recognition that they were rich. But the only thing worse than not being on the list of the UK's 1,000 wealthiest people was being lower than your ego demanded. Bust someone down to the 900s when they felt they should be in the 800s was a grave insult punishable by yet another phone call from a PR flunky.

The list, published on Monday, saw Mexico's Carlos Slim retain the top slot for the fourth straight year with a net worth of $73bn.

The 10th spot on the list went to Bernard Arnault and family of the luxury goods group LVMH, with a net worth of $29bn.

Severed ties

Prince Alwaleed's office claimed the magazine used flawed valuation methods that were "designed to disadvantage" Middle Eastern investors.

It alleged that the magazine had refused to accept the valuations of the stocks listed on Tadawul, the Saudi Arabian Stock Exchange, while it had accepted valuations of listings on other emerging markets such as the Mexican Stock Exchange.

It said that Forbes had applied "differing standards of proof for different individuals".

The prince's office said that it had requested Forbes to remove the prince from its rich list. It added that it had severed all ties with the magazine and would no longer co-operate with the valuation teams.

"We have worked very openly with the Forbes team over the years and have on multiple occasions pointed out problems with their methodology that need correction," Shadi Sanbar, chief financial officer of Kingdom Holding Company, which the prince owns, said in a statement.

"However, after several years of our efforts to correct mistakes falling on deaf ears, we have decided that Forbes has no intention of improving the accuracy of their valuation of our holdings and we have made the decision to move on."

The prince's Kingdom Holding Company, whose shares are traded on the Saudi stock exchange, owns stakes in hotel groups including Four Seasons and Fairmont Raffles and is a part-owner of the Savoy Hotel in London.

The prince is a major investor in News Corporation and, according to Forbes, he bought a 3% stake in Twitter last year for $300m.