lived, analysts said. "Continuing oil demand growth has led to tightness throughout the oil supply chain and created an environment in which the desire to hold higher stocks and fears of a supply disruption are driving oil prices," said the London-based CGES. With some production in the UK North Sea and India offline, dealers fear OPEC -- already pumping nearly flat out -- would strain to make up for any unexpected outages during the Northern Hemisphere winter, when demand peaks. "OPEC will need to keep production above 30 million bpd to keep pace with the call on its oil, which has been boosted by a poorer than anticipated performance by non-OPEC producers so far this year," said the CGES report.