European stocks extended their losses in afternoon trade on Wednesday, with tech and mining shares among the biggest laggards, as U.S. stock futures pointed to a lower opening on Wall Street.

At 1223 GMT, the pan-European FTSEurofirst 300 index was down 0.66 percent, at 1,496.97, surrendering some of Tuesday's hefty gains.

Miners were on the downside, retreating along with base metal prices. BHP Billiton shed 2.7 percent, while Anglo American dropped 2.4 percent.

Tech stocks were also under pressure as U.S. firm Texas Instruments Inc left its outlook unchanged, halting a trend of improving forecasts among tech firms.

Nokia fell 3 percent.