Iraq's government has opened six major oil fields to bids from foreign companies, including BHP Billiton.

Our Middle East correspondent, Ben Knight, reports the tenders would give the world's major oil companies access to Iraq's massive reserves through technical services contracts.

It was expected the deals would be signed on Monday, but instead Iraq's government has announced it will open the oil fields to bids from thirty-five companies, offering long-term contracts.

The surging price of oil makes Iraq a major target for oil companies.

Bidders must have an Iraqi partner and give 25 per cent of the value of the contracts to Iraqi companies.

Shell, which heads a consortium including BHP, hopes the deal can be done within weeks, seeing the return of major oil companies to Iraq for the first time since the industry was nationalised 36 years ago.

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