Iraq’s oil potential is larger than earlier understood, US President Barack Obama’s national security adviser said today.

“They have discovered more reserves and it looks like the aggregate possibilities are even bigger than we previously thought,” James Jones said in a brief interview after a speech at the US Chamber of Commerce in Washington.

Jones, who formerly headed the Chamber’s Institute for Energy, told Reuters that exploration is “yielding more reserves” as it becomes easier to move around Iraq.

He spoke at the Chamber about the investment possibilities in Iraq as security improves.