•Global crude futures prices moved up strongly Tuesday with no immediate headline to cause the spike and amid trading volumes ahead of the Thanksgiving national holiday in the US, market sources said.

•"There is low volume today, the market is just winding down," said a London-based broker. "After the US inventory data on Wednesday, I think people will just start to disappear from the market." When trading volume is lower than usual, there is potential for greater swings in price as market participants have a greater influence on price movement.

•Some market commentators pointed to a possible cut in US interest rates and the resulting weaker dollar as another source of Tuesday's strength in oil futures.

Updated: November 20, 2007