Brent crude futures slumped to a four-year low today, below $90 a barrel, as increasing supply and a poor worldwide economic outlook proved too much pressure for oil prices.

Reuters reported that Brent crude for November delivery declined 45 cents to $89.60 a barrel and US November crude dropped $1 to $84.77 a barrel.

"Germany may trim its growth forecasts next week for this year and 2015 due to concerns of a recession."

Two sources in Germany’s ruling coalition said that the country may trim its growth forecasts next week for this year and 2015 due to concerns of a recession.

Earlier this week, data revealed that German exports declined the most in August, since January 2009.

China is also showing signs of a slowdown. The country’s data, which is scheduled to be revealed next week, may indicate that weak domestic demand probably slowed growth in its imports.

Meanwhile, US crude inventories increased far more than anticipated last week amid higher imports and cuts in refineries’ production.

The latest developments have increased pressure on the Organization of the Petroleum Exporting Countries (OPEC) members to take steps to decrease supply.

Analysts, however, say OPEC is unlikely to take a decision before its meeting in November, due to be held in Vienna, Austria.

Reuters reported that several OPEC members are not willing to cut the output as they do not want to lose market share to other countries.

PetroMatrix managing director Olivier Jakob was quoted by the news agency as saying: "They’re all fighting for market share through the official selling prices.

"They’re really not showing any signs, and Saudi Arabia has not shown any signs, that they will cut production."