IF THEY sound worried, it is because they are desperate.

The multinational oil companies are rolling in cash but they have little to spend it on. Demand for fossil fuels is growing at a spanking pace, the price of a barrel has risen to record levels and you might think it was Christmas every day for a company such as ExxonMobil.

Instead, big oil is fretting. According to Deutsche Bank, the Western oil majors will together accumulate about $45 billion (£25.3 billion) in spare cash after investing in projects, paying their bills, taxes and the annual dividend.

A prudent oil chairman, you might think, would see that it was time to think long term, to invest for the distant horizon, spend a little more and stash away some fossil fuels for the future. Lee Raymond, the ExxonMobil chairman, is a prudent man but he, like BP, Total and Shell, is not pushing the boat out. Spending is up, a little, but if President Bush is hoping that the oil majors will ride to the rescue of the American economy with a spending spree, he is mistaken.

The problem is there is nothing to buy. The oilfields of the North Sea, Texas and Alaska are drying up. There are interesting prospects in West Africa and the Gulf of Mexico, but the big opportunities are in Saudi Arabia, Kuwait, Iran and Iraq, tantalising and unavailable.

The national oil companies of the Middle East and Venezuela view the ExxonMobils and BPs with suspicion.

The International Energy Agency gives warning that $400 billion (£225 billion) needs to be invested in the Middle East over the next two decades if we are to have the oil supplies we need. That is unlikely to impress the Opec governments. They are by instinct hoarders — for them ownership of the resource is key. Led by corrupt elites, the Opec states of the Middle East are happy to run the cartel, micro-manage the oil price, collect the rent from selling barrels and watch their economies decline.

It is an awkward truth. The world’s greatest oil company is not ExxonMobil, but Saudi Aramco. It is the Opec national oil companies, and possibly Gazprom of Russia, that will drive investment or the lack of it over the next 20 years. You have been warned.

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