Before the discovery of oil, and more recently natural gas within its borders, Qatar’s economy was driven by fishing and pearls. It has now become the country with the highest GDP per capita in the world, according to the IMF.

Up to a third of the world's total gas reserves lie in Qatar, and it produces around 800,000 barrels of oil each day. Production is expected to have topped a millon barrels per day by 2011. Almost all of Qatar's wealth is focused in the capital Doha and its main suburb Al-Rayyan, where 83 per cent of Qatari residents live.

For decades, Qatar's ruling family, the Al Thanis, was content to sit and watch the dollars flow in. In 2003, the Qatari Investment Authority (QIA) was set up to diversify assets into overseas markets. Emir and Prime Minister, Sheikh Hamad bin Jassim bin Jabr Al Thani, who came to power in 1995 after deposing his father in a bloodless coup, wanted to ensure that his country’s wealth would survive after its oil supply dries up.

Qatar's assets have almost doubled since 2005 after a blue-chip spending spree that includes a stake in Swiss bank Credit Suisse in February, a 15 per cent stake in the London Stock Exchange, purchased in September 2007, and 6 per cent of French media and aerospace conglomerate Lagardere. It was also in discussions to take over British supermarket giant Sainsbury’s last year through its investment vehicle Delta Two, and still owns 24.9 per cent of the chain.

Sheikh Al-Thani said earlier this year that the QIA will spend between £5 billion and £7.5 billion on stakes in banks, adding that it preferred European banks because American financial institutions were more exposed to sub-prime mortgages.

Real estate is another area the QIA is involved in – it has a significant holding in Canary Wharf and the new Shard of Glass development by London Bridge, and is involved in a huge mall development in Kuala Lumpur. It also owns four UK nursing home chains, including Four Seasons Healthcare.

Doha is establishing itself as a financial centre through the local stock exchange, the Doha Securities Market, and the Qatar Financial Centre Authority. The government has embarked on an ambitious building programme that will see two new cities built in the desert around Doha, as well as new research and science parks, to attract European and American companies.

The high price of oil and natural gas means that the Al-Thani family will soon have plenty of money to add to the $60 billion (£30 billion) already held by the QIA. Its £1.76 billion stake in Barclays is unlikely to be the last major investment it makes in the UK.

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