Global oil demand will collapse next year and commodities will not return to the highs they reached this summer in the foreseeable future, two authoritative reports said yesterday as they forecast a long and painful worldwide recession.

The stark conclusions came as the World Bank’s chief economist predicted that the world faced “the worst recession since the Great Depression”.

The US energy department said global oil demand will fall this year and next, marking the first two consecutive years’ decline in 30 years. “The increasing likelihood of a prolonged global economic downturn continues to dominate market perceptions, putting downward pressure on oil prices,” it said, forecasting that demand would drop 50,000 barrels a day this year and a hefty 450,00 b/d in 2009. US oil demand will drop next year to the lowest level in 11 years.