* Asian stocks lower following negative lead from Wall St
* Nikkei further hit by stronger yen
* Dollar reaches six-week lows versus Japanese currency
By Ian Chua
SYDNEY, Aug 7 (Reuters) - Asian stocks fell to their lowest since mid-July early on Wednesday following a second day of losses on Wall Street as uncertainty about when the Federal Reserve will start to reduce stimulus kept a leash on market bulls.
The dollar ground lower against a basket of major currencies. It hit a six-week low against the yen, which in turn weighed on Japanese stocks.
MSCI's broadest index of Asia-Pacific shares outside Japan lost 0.4 percent, extending a 0.5 percent decline on Tuesday to trade at their lowest since July 19.
Tokyo's Nikkei shed 2.4 percent to trade at one-week lows, with exporters such as Toyota Corp losing ground on concerns the stronger yen would erode their dollar earnings when repatriated.
"Because trading volume is likely to be thin, the cash market will likely be swayed by futures trading. The market is keeping an eye on the yen's level as that has been the cause of recent volatility," said Yutaka Miura, a senior technical analyst at Mizuho Securities.
The weaker start for Asian bourses came after the U.S. S&P 500 index eased 0.6 percent.
Investors keen on clarity on when the Fed might start to scale back its bond-buying programme were left sorely disappointed after comments from two top Federal Reserve officials shed no new light.
"(The Fed officials comments) are inserting uncertainty to the market where foreign investors are expected to position themselves as sellers," said Choi Kwang-hyeok, a market analyst at E-Trade Securities about South Korean stocks.
Indeed, uncertainty about the Fed's tapering plan, thin trading conditions and a lack of fresh impetus conspired to keep the greenback pinned down against a basket of major currencies.
The dollar index held near a one-week low as the greenback slid to 97.09, a level last seen on June 25. The euro was flat at $1.3299, but not far from a one-week high around $1.3323 set on Tuesday.
Commodities were mostly subdued, with copper slipping 0.3 percent to $6,987 a tonne, giving back most of the gains made on Tuesday.
U.S. crude was little changed at $105.43 a barrel, while gold touched a three-week low around $1,274 an ounce, extending Tuesday's 1.7 percent slide.
There is little major economic data out of Asia on Wednesday. The key focus is the Bank of England's inflation report, in which it is expected to assure markets that it will keep interest rates at rock-bottom levels for an extended period.
On Thursday, the Bank of Japan will announce the outcome of its two-day policy review, and is widely expected to press on with its massive asset buying program.
Recent data showed the world's third-biggest economy is starting to stir thanks to the BOJ's unprecedented quantitative easing push and government fiscal stimulus.