The New York Times has been blocked in China for reporting that premier Wen Jiabao's family have controlled assets of at least $2.7bn (£1.67bn). The report is particular embarrassing for Wen because he has made a point of stressing his modest background.
The issue of politicians' financial worth is almost as sensitive in the US and UK, as voters in those countries continue to suffer from the economic crisis. In the US presidential race, Barack Obama has attempted to paint his opponent, Mitt Romney, as out of touch with mainstream American life partly because of the vast wealth the Republican accumulated during his business career. The president told Romney during one of the presidential debates:
In Britain Labour leader Ed Miliband attacked David Cameron for giving "a tax cut to millionaires" (in fact it is a tax cut for those earning more than £1m a year) and for benefiting from that tax cut himself, implying that the prime minister was either a millionaire or earned more than £1m a year.
But Obama and Miliband's own estimated wealth, while less than their opponents', arguably insulates them just as completely from the concerns of ordinary taxpayers.
It is very difficult to calculate the true wealth of political leaders; few, if any, are prepared to give comprehensive details of their earnings and assets. However, estimates have been made for most world leaders. Here are the highlights.
The New York Times report that the family of Wen Jiabao (left) has at least $2.7bn (£1.7bn) in controlled assets comes at a sensitive time for China's leaders as they prepare for their once-in-a-decade transition of personnel: recent reports have also claimed that relatives of Xi Jinping, the man expected to be China's next president, had assets worth millions of dollars (that report got Bloomberg blocked in China) and that the family of disgraced politician Bo Xilai had at least £136m in assets.
The Sultan of Brunei
The Sultan of Brunei, Hassanal Bolkiah (left), may be the world's richest head of government, with an estimated wealth of $20bn, although Forbes warned:
With only about 25 years of estimated oil reserves left, the Sultan has yet to launch any significant attempts to diversify the Brunei economy beyond oil.
A Forbes list of the world's richest royals puts the King of Thailand, King Bhumibol, above the Sultan with $30bn, much of it built up through investments in companies such as Siam Cement and Siam Commercial Bank, although Bhumibol does not have political control of his country.
Sebastián Piñera (left), the president of Chile, may be the richest non-royal leader in the world, with an estimated worth of $2.4bn, much of it from investments. Asif Ali Zardari, the president of Pakistan, is thought to be second with an estimated net worth of $1.8bn.
In December the Russian president (left) declared his income as $115,000 and his bank balance $179,612.
But his opponents have claimed over the last few years that he has secretly accumulated over $40bn while in office and is therefore actually Russia's richest man. My colleague Luke Harding wrote in 2007:
In an interview with the Guardian, [Russian political expert Stanislav] Belkovsky repeated his claims that Putin owns vast holdings in three Russian oil and gas companies, concealed behind a "non-transparent network of offshore trusts".
Putin "effectively" controls 37% of the shares of Surgutneftegaz, an oil exploration company and Russia's third biggest oil producer, worth $20bn, he says. He also owns 4.5% of Gazprom, and "at least 75%" of Gunvor, a mysterious Swiss-based oil trader, founded by Gennady Timchenko, a friend of the president's, Belkovsky alleges.
Asked how much Putin was worth, Belkovsky said: "At least $40bn. Maximum we cannot know. I suspect there are some businesses I know nothing about."
As of 2011, the most recent year it has produced figures for, the Center for Responsive Politics, a research group examining the role of money in US politics, estimated Obama's net worth to be somewhere between $1.6 and $7.7m. This is based largely on sales of his bestselling books, Dreams from my Father and The Audacity of Hope. Obama (left) earns $400,000 a year as president, and declared a joint income for himself and his wife Michelle of $1,728,096 for 2011:
Today, the president released his 2010 federal income and gift tax returns. He and the first lady filed their income tax return jointly and reported an adjusted gross income of $1,728,096. The vast majority of the family's income is the proceeds from the sale of the president's books. The Obamas paid $453,770 in total federal tax.
The president and first lady also reported donating $245,075 – or about 14.2% of their adjusted gross income – to 36 different charities.
The Center for Responsive Politics estimates Romney (left) to be worth between $80.9 and $256m (2011 figures), thanks to his business career and investments. Romney has declared he earned $13.7m in 2011.
The Daily Mail has estimated David Cameron's worth to be £4m, based on the value of the Camerons' London home (estimated at £2.7m) and their constituency home (£1m). Cameron's salary as prime minister is £142,500:
The PM and his wife both come from wealthy backgrounds and enjoy substantial property assets of their own: their London home has been valued at £2.7million and their constituency house at £1million. Mrs Cameron's work as the creative director of Smythson, the upmarket stationers, earned her a £300,000 bonus. Both are in line to inherit fortunes from their parents: the combined wealth of the Camerons' parents has been put as high as £30million.
According to the Daily Telegraph, Ed Miliband (left) owns property estimated to be worth more than £1m, and is reported to have come into an inheritance from his late father. Miliband has avoided answering questions about how much he is worth, saying only: "I am not going to be getting the top rate tax cut," meaning he earns less than £150,000. As leader of the opposition, he is paid £128,836 a year.
The Saudi royal family, which pools its wealth, is estimated to be worth over $1.4tn as a result of the country's vast oil industry. Forbes reported last year that King Abdullah (left) was worth $18bn, writing:
Another of the relatively few ruling monarchs, King Abdullah Bin Abdul-Aziz is head of a prodigious family and is estimated to be worth about $18 billion. Though there has been rampant speculation on the health of Saudi Aramco (the state-owned oilmonopoly) and the size of its remaining reserves, the Saudi royal family has been quite active in investing much of its oil-generated wealth into other businesses outside the country.
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image: © World Economic Forum