By Sara Sjolin, MarketWatch

LONDON (MarketWatch) -- U.K. stocks moved higher for a second-straight session on Wednesday, as energy firms advanced on the back of higher oil prices.

The FTSE 100 index climbed 0.61% to 6,402.17, building on a similar gain from Tuesday. The broader European markets were also on the rise, with all eyes on the Fed. The Federal Open Market Committee is expected announce an end to its bond-buying program, but vow to keep rates low for a considerable amount of time, in a decision expected at 2 p.m. Eastern Time, or 6 p.m. London time.

Oil firms were among biggest advancers, tracking a jump in crude-oil prices (CLZ4) that jumped 1.4%. Shares of BP PLC (BP) gained 1.6%, Royal Dutch Shell PLC (RDSB) added 1.3% and BG Group PLC picked up 1.7%.

Mining shares also rose, with shares of Randgold Resources Ltd. up 1.3%, Glencore PLC rising 1.4% and Anglo American PLC adding 1.2%.

On a more downbeat note, shares of Next PLC lost 0.4% after the clothing retailer cut its full-year pretax profit guidance.

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