LONDON Shell's refining profit margins dropped by nearly 30% in the third quarter from the previous three months as global demand sagged, while oil product trading earnings also weakened, it said on Monday.

A drop in refining margins in recent months, a result of slowing global economic activity and new refineries coming on line, is set to weigh on third quarter earnings of the world's top energy companies.

In a trading update ahead of its quarterly results on Oct 31, Shell said its indicative refining margins dropped to US$5.50 a barrel in the three months to the end of September from US$7.70 a barrel in the previous period.

Trading results for its chemicals and oil products division were expected to be lower than in the second quarter, Shell said.

Shell processed around 1.4 million barrels per day of crude oil in its refineries in the second quarter, roughly 1.2% of global oil demand.

Shell, the world's largest trade

r of liquefied natural gas, also lifted its LNG production guidance for the quarter to a range of 7.3 million to 7.7 million metric tons from a previous forecast of 6.8 million to 7.4 million tons.

LNG trading results were set to be in line with the previous quarter.

Last week, Exxon Mobil warned that a slump in oil prices was set to hit its third-quarter results.

Oil prices fell by 17% in the third quarter, the largest quarterly decline in a year, on worries about the global oil demand outlook. Brent futures settled at US$71.77 a barrel on the last trading day of the quarter.

Jefferies analyst Giacomo Romeo said Shell's analyst consensus adjusted earnings for the quarter could fall by about 10% from around US$5.5 billion following the update.

The London-listed company also lifted its upstream oil and gas production outlook for the quarter to 1.74 million to 1.84 million barrels of oil equivalent per day (boed) from 1.58 million to 1.78 million boed.

  - Reuters