ExxonMobil and Royal Dutch Shell, the world's two biggest western oil companies, yesterday won the right to develop Iraq's giant West Qurna oilfield, raising the prospect of a big jump in Iraqi oil supplies over the coming years.

The agreement is the third such deal this year and marks the first time a US-led consortium will re-enter Iraq's oil industry in more than 30 years. It is a blow to Lukoil of Russia, which had signed an agreement to develop West Qurna under Saddam Hussein and has been lobbying intensely for the field in the past weeks.

Hussein Shahristani, Iraq's oil minister, has said he is now confident that within seven to 10 years his country will be able to boost its production of little more than 2m barrels a day to almost 10m b/d, more than 10 per cent of today's total global oil production. In the past, analysts doubted the target was achievable, mainly because of Iraq's difficult security and political climate. But even they agree now that the big increase is feasible.

A recent note by PFC Energy, the industry consultants, points out that the extra oil foreign energy companies, such as Exxon, BP and Eni, have promised to tease out of other Iraqi oilfields adds up to about 4.7m b/d, while the fields that are likely to go under the hammer at Iraq's next oil auction, will add at least another 3m b/d.

Even well before the middle of the next decade, Iraq will be able to raise its production enough that the Organisation of Petroleum Exporting Countries, the cartel, might have a big conundrum on its hands, PFC said.