The premier index was little changed at 6,501.42, up just 0.28 points. By comparison, Germany’s Dax and France’s Cac, which have less exposure to oil producers, were up over one per cent.
The FTSE 100 has fallen one per cent so far in January, extending December’s 2.3 per cent drop.
Brent oil fell five per cent, dropping below $48 a barrel to near six-year lows following a cut in short-term forecasts by Goldman Sachs.
The UK oil and gas index, which features major oil companies such as Royal Dutch Shell and BP, was down 1.5 per cent, extending falls after US stocks dipped in early trade.
GKN rose 3.2 per cent, after Credit Suisse raised its price target for the stock to 410p from 380p and reiterated its “outperform” rating.
Domestic energy suppliers came under pressure. SSE fell 5.8 per cent, the biggest loss in the FTSE 100 index.