Saudi Arabia failed to provide the United States with any new promises or assurances over oil supplies ahead of a key meeting between Crown Prince Abdullah and George W. Bush at the president's ranch in Crawford, Texas on Monday.

Mr Bush voiced concerns this week about Saudi Arabian production and the country's ability to increase output in the event of a severe supply disruption. His comments are the most vocal since he became president, and mark a departure from protocol by a US president about the world's biggest oil exporter, and former special friend.