The Organisation of Petroleum Exporting Countries signalled a significant tightening of oil markets towards the end of this year, warning on Wednesday it would have to pump close to its maximum capacity next winter to meet rising demand from China against the backdrop of slowing Russian production.

The cartel said it would have to supply at least 30.1m barrels a day in the fourth quarter of the year to balance the market, an increase of 630,000 b/d from its previous estimate in January and 1.1m b/d up from the December figure. The International Energy Agency forecasts Opec's capacity will be 31.5m b/d by mid-2005.