European shares closed down on Wednesday, as investors looked ahead to the release of minutes from the Federal Reserve's July policy meeting.
The pan-European FTSEurofirst 300 Index provisionally closed down 0.6 percent at 1,207.57, despite shares of Danish wind turbine manufacturer Vestas Wind Systems surging 5.42 percent after reporting a positive outlook for the second half of the year. Vestas also said it was replacing current CEO Ditlev Engel.
(Read more: Denmark's Vestas replaces embattled CEO Engel)
In Asia, shares pared early gains on Wednesday, following heavy losses in many markets on Tuesday amid concerns over a potential reduction in monetary stimulus by the U.S. central bank.
In the U.S., stocks opened lower on Wednesday, with the Dow headed for its sixth-consecutive session in the red, ahead of the Fed minutes. The minutes, due at 7 p.m. London time, could provide fresh clues on the central bank's future policies, with some expecting the Fed to start slowing the pace of its asset purchases as soon as next month.
Britain's benchmark index, the FTSE 100, fell for the third straight day, closing down 1 percent and touching six-week lows. Heavyweights HSBC and British American Tobacco closed sharply lower.
(Read more: Asian shares trade mixed ahead of Fed minutes)
In Europe, German finance minister Wolfgang Schaeuble said Greece would need a third bailout, during an election campaign event in Hamburg, breaking something of a taboo of mentioning the unpopular topic of Greece ahead of the country's federal elections on September 22 .
"There will have to be another program in Greece," in order to help the country "get over the hill" of debt financing that it still faces, Schäuble said.
In stock news, shares in waste group Veolia closed up roughly 8.32 percent after an upgrade from Morgan Stanley, with analysts raising their recommendation to overweight from equal-weight, saying the company was the most attractive turnaround story in the sector.
Shares of Dutch brewer Heineken fell by 3.98 percent after it said subdued consumer confidence in Europe and the U.S. had weighed on first-half earnings.
(Read more: Heineken profits from developing markets surge)
Shares of fellow brewer Carlsberg slipped by 1.6 percent after it reported a hit to net profit from weakness in Russia and Western Europe.
(Read more: Russia gives Carlsberg a hangover)
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