By Carla Mozee, MarketWatch

LONDON (MarketWatch) -- U.K. stocks turned lower Thursday, heading for their fourth consecutive decline, led by another round of pullbacks for mining companies.

The FTSE 100 fell 0.8% to 6,449.36. The FTSE 100 index on Wednesday marked the first time in two months that it lost ground in three straight sessions, noted Bill McNamara, technical analyst at Charles Stanley, in a report early Thursday. The FTSE 100's closing at session lows on Wednesday "strongly implies that it has further to fall in the near term," he wrote. "Hopes of a 'Santa rally' are fading fast."

U.K. stocks on Thursday turned lower alongside the broader European market, where tepid demand among banks for cheap loans from the European Central Bank added another layer to the lackluster-growth picture in the eurozone, the U.K.'s main trading partner.

Bearing the brunt of the turnaround in London trade was the basic materials sector, which fell 3% as nearly all mining stocks fell at least 1%. At the bottom of the FTSE 100, Randgold Resources Ltd. fell 4.6%, Fresnillo PLC gave up 4.1% and Anglo American Ltd. shed 3.5% following a ratings downgrade at BNP Paribas to underperform from neutral.

In the energy space, BG Group PLC fell 2.6% and Tullow Oil PLC declined 2%. But shares of Royal Dutch Shell PLC and BP PLC were each off 0.2%, respectively, and have been darting between small gains and losses.

Shares of energy-engineering firm Weir Group PLC were also bouncing between gains and losses, and were recently down 0.1%. The energy engineering firm was downgraded at Citi Research to neutral from buy, as the 35% drop in oil prices since September "has driven a deteriorating earnings outlook," for Weir, wrote analyst Andrew Simms in Thursday note.

Meanwhile, shares of Sports Direct International PLC fell 1.7%. They had been higher earlier in the session after the retailer posted a 5% rise in first-half pretax profit.

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