(Close): Oil companies were among the biggest fallers on the FTSE 100 as oil prices languished at four-year lows.
Tullow Oil was the worst performer on the index, shedding 6%, while Royal Dutch Shell "A" and "B" shares were both down more than 2%.
Meanwhile, Brent crude futures fell to $79.32 a barrel as further data on China's slowing economy pointed to weaker global demand for oil.
Overall, the FTSE 100 index closed up 24.41 points or 0.4% at 6635.45.
Electronics retailer Dixons Carphone rose 2.3%, on expectations of a busy Christmas period.
On the currency markets, the pound was down 0.34% against the dollar at $1.5727 and fell 0.65% against the euro to €1.2604.
