Britain's Serious Fraud Office has demanded documents from GlaxoSmithKline, AstraZeneca and Eli Lilly (NYSE:LLY) and Co., the British affiliate of the Indianapolis drug firm, London's The Independent said.

The companies have denied wrongdoing and said they plan to cooperate with investigators, the newspaper said.

All three are accused of paying to secure lucrative contracts, violating the United Nation's oil-for-food program, the newspaper said.

The program required that proceeds from Iraq oil sales were to go for food and medicine to ease the effect of sanctions against Saddam's regime following the 1990 Kuwait invasion, it said.