Every sector was either trading flat of registering a loss on Monday as European and US debt concerns sparked a mass sell-off.Oil equipment, services and distribution stocks were the worst performers as oil prices sank for the third day. The Finance Ministry of Japan, the third-largest crude oil consumer, revealed that exports fell by an annual rate of 3.7% last month, the first decline in three months, as shipments to China, the US and Europe weakened.Meanwhile, Chinese Vice Premier Wang Qishan warned that the global economy could be hit by a long recession. "Amid uncertainties, the one thing we can be sure of is that the global recession caused by the international financial crisis will be extended," Wang was quoted as saying by Xinhua News Agency.By 14:42, the Brent crude spot price on the IntercontinentalExchange (ICE) was down 0.86% at $106.99 on fears of a global slowdown and concerns over demand.Petrofac, Wood Group, Hunting and Amec were the worst performers in the sector.The gas, water and multiutilities sector was falling by an average 0.3% and was therefore the best performing sector of the day.Centrica was among the few bright spots on the FTSE 100 today after signing a deal with the Norwegian company Statoil to buy £13bn worth of gas over ten years. In a separate transaction, Centrica has also announced it is to buy some of Statoil's assets in the Norwegian sector of the North Sea for £965m, with a further £63m to be paid on the future performance of the assets. Sector peer Severn Trent was also eking out small gains.BCTop performing sectors so far todayBottom performing sectors so far todayOil Equipment, Services & Distribution 20,750.11 -4.20%Mining 19,028.98 -3.86%Personal Goods 19,247.46 -3.43%Technology Hardware & Equipment 697.02 -3.40%Forestry & Paper 4,631.68 -3.31%