Futures decline amid renewed Fed tapering concerns

U.S. stock index futures indicated a lower open on Wednesday amid renewed concerns about when the Federal Reserve will begin tapering off its asset purchases.

(Read more: Early movers: TimeWarner, Devon, AOL & More)

On Tuesday, two Fed presidents — Charles Evans and Dennis Lockhart — said the central bank would likely start reducing its stimulus program as early as September. U.S. stocks logged their biggest drop since June after the comments.

(Read more: Fed may cut bond buying as soon as next month, Evans)

More Fed officials are scheduled to speak, with Philadelphia Fed President Charles Plosser at 12:30 pm ET on the economic outlook, and Cleveland Fed President Sandra Pianalto at 1:40 pm on the regional economy.

On the economic front, mortgage applications edged up last week as potential buyers crept back into the housing market even though rates continued to climb, according to the Mortgage Bankers Association.

The Fed will also release consumer credit data for June at 3 p.m. Analysts polled by Reuters forecast a $15 billion gain, after a $19.6 billion rise in May.

The government is scheduled to auction $24 billion in 10-year notes with the results available shortly after 1 pm ET, following Tuesday's strong $32 billion 3-year note auction.

(Read more: Fed may cut bond buying as soon as next month, Evans)

"We're entering the dog days of August and that tends to benefit the Treasury market," said John Briggs, senior Treasury strategist with RBS.

Among earnings, Walt Disney declined after the media conglomerate edged past earnings expectations but projected a massive loss related to its summer film, "The Lone Ranger." Analysts were mixed on the stock—Bernstein raised its price target on the company to $76 from $73, while RBC cut its target price to $71 from $72.

Time Warner rose after the media corporation beat earnings and revenue forecasts. In addition, the company said it expected mid-teens percentage earnings growth for the full year, up from the low double-digit estimates it previously provided.

Meanwhile, First Solar slumped after the solar company posted quarterly results that were below expectations and cut its full-year outlook.

Groupon, Green Mountain Coffee Roasters, Mondelez International, Tesla Motors and Transocean are among notable companies slated to post results after the closing bell.

In Asia, the Nikkei ended below the key 14,000 level and the Japanese yen hit a six-week high against the dollar. Australia's S&P ASX 200 index and South Korea's Kospi hit two-week lows.

Meanwhile, the Bank of Japan began a two-day policy meeting on Wednesday with an outcome due on Thursday. While analysts expect no action, the direction of the yen will hinge on the central bank's statement.

Shares in Europe also fell on Fed concerns on Wednesday, and in the U.K., investors were focused on Bank of England Governor Mark Carney's first inflation report.

Carney unveiled Fed-style forward guidance, and said Britain's central bank will not raise interest rates until U.K. unemployment hits 7 percent.

"When Carney came in everyone expected him to be quite dovish; in fact it didn't turn out that way. He is embarking on a new path for the Bank of England," said Khoon Gon, senior FX strategist at ANZ.

—By CNBC's JeeYeon Park (Follow JeeYeon on Twitter: @JeeYeonParkCNBC)

Coming Up This Week:

WEDNESDAY: Oil inventories, Fed's Plosser speaks, 10-yr note auction, Fed's Pianalto speaks, consumer credit; Earnings from Green Mountain Coffee Roasters, Groupon, Mondelez Int'l, Tesla Motors, Transocean
THURSDAY: Jobless claims, natural gas inventories, Fed balance sheet/money supply, chain store sales; Earnings from Rio Tinto, Dean Foods, T-Mobile, Lions Gate Entertainment, Nvidia, Priceline.com, Annie's
FRIDAY: Wholesale trade

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