The FTSE 100 index was flat on Tuesday as markets awaited Wednesday's Federal Reserve's decision on interest rates, and with British Energy a standout loser on fears over repairs to two of its nuclear generators.
Oil prices around $64 a barrel helped BP and Shell weather news of legal wrangles and upheaval in Russia and for BP continuing concerns over production at its Thunder Horse oil and gas field in the Gulf of Mexico.
Royal Dutch Shell added 0.8 percent despite the Russian government cancelling environmental permits that would allow the company to develop the second stage of the Sakhalin 2 offshore project. BP shares rose 1.6 percent.
By 08:31 GMT (9:31 a.m. British time) the FTSE 100 was 4.4 points or 0.07 percent lower at 5,886.3 points.
Miners also supported the market, with the commodity prices buoying the sector. Kazakhstan's biggest copper miner Kazakhmys ticked up 1 percent ahead of reporting first half earnings today. Also in the sector, Anglo American , BHP Billiton and Rio Tinto were all up about 1 percent.