Rising global oil prices are bolstering the power of America's enemies around the world, strengthening the regimes in Iran, Syria, Sudan and Venezuela and increasing Russia's assertiveness in eastern Europe, US intelligence agencies said on Thursday.

Two days after President George W. Bush called for the US to end its "addiction to oil", John Negroponte, the Director of National Intelligence, said the combination of rising demand for energy and instability in oil-producing regions "is increasing the geopolitical leverage of key producing states".

Negroponte said in testimony to the Senate Select Committee on Intelligence, that the most important election on the African horizon will be held in spring 2007 in Nigeria, the continent's most populous country and largest oil producer. The vote has the potential to reinforce a democratic trend away from military ruleย—or it could lead to major disruption in a nation suffering frequent ethno-religious violence, criminal activity, and rampant corruption.

He said that speculation that President Obasanjo will try to change the constitution so he can seek a third term in office is raising political tensions and, if proven true, threatens to unleash major turmoil and conflict. Such chaos in Nigeria could lead to disruption of oil supply, secessionist moves by regional governments, major refugee flows, and instability elsewhere in West Africa.