Asian markets dropped to four-week lows on Wednesday as renewed Federal Reserve stimulus fears dampened sentiments.

The Japanese Nikkei was trading 3.64% lower or 524 points to 13,877.06.

Australia's S&P/ASX index was trading 1.91% lower or 97.70 points to 5007.90

The Shanghai Composite index was trading 0.31% lower or 6.31 points to 2,054.19

Hong Kong's Hang Seng was trading 0.99% lower or 217.65 points to 21706.05.

South Korea's Kospi was trading 1.18% lower or 22.55 points to 1,884.07 points.

Market participants await clarity on the timing of the US Federal Reserve's planned quantitative easing tapering. However, comments from two top Fed officials on Tuesday failed to provide it.

Atlanta Fed president Dennis Lockhart said the initial cut back in the central bank's asset-buys could start at any of the three remaining Federal Open Market Committee (FOMC) meetings this year. Elsewhere, Chicago Fed President Charles Evans agreed that the central bank will possibly cutback on its bond-buying programme later in 2013.

The FOMC is due to meet on 17 September, 29 October and 17 December. The September and December meetings will be followed by a news conference by Fed Chairman Ben Bernanke.

In Japan, the country's central bank has kicked off a two-day meeting and is widely expected to continue with its asset buys.

Wall Street Down

On Wall Street, Fed jitters forced investors to sell. The Dow finished 93.39 points lower at 15,518.74, pulled down by IBM and Hewlett-Packard.

The S&P 500 closed 9.77 points lower at 1,697.37, while the Nasdaq ended 27.18 points lower at 3,665.77.

The US Federal Reserve remains determined to start trimming its $85bn bond-buying programme later this year but remains tight-lipped about when the planned reduction will take place. On 31 August, a Fed statement said the central bank will continue buying mortgage and treasury securities to further strengthen the US economy which it said was still challenged by federal austerity measures.

A cutback in monetary stimulus could lead to a detrimental knock-on effect for emerging markets. A reduction in QE would raise bond yields in the US, which in turn would raise eurozone rates and suck out money from emerging markets.

A sudden withdrawal of foreign funds from emerging markets could also be catastrophic, as has happened before, during the Asian and Russian financial crises of 1997 and 1998 respectively.

Company Stock Movements

In Tokyo, audio technology firm Pioneer dropped 6.7% after it reported a higher quarterly loss and slashed its full-year profit forecast by more than 90%.

A stronger yen hurt exporters' stocks. Semiconductorcompany Tokyo electron fell 4.6%. Camera-maker Olympus dropped 4.2%. Diversified miner Sumitomo Metal Mining lost 3.8% while consumer electronics major Sony was down 2.9%

Suntory Beverage and Food, which debuted in Tokyo last month, shed 1.8% even after it reported an almost doubling of its first-half profit.

Energy major Showa Shell Sekiyu shot up 6.4% after it raised its full-year profit outlook by 85%.

In Sydney, gold miner Newcrest Mining dropped 4.2% after the benchmark Comex gold futures fell below the $1,300-an-ounce level on Tuesday.

Uranium extractor Paladin Energy fell 4.2% while iron-ore miner Fortescue Metals lost 2.8%

Macquarie Group lost 2% while National Australia Bank was down 1.3% following the Reserve Bank of Australia's decision to cut interest rates.

Movie producer 21st Century Fox jumped 1.5% after it reported a 16% jump in revenue for the quarter ended June.

In Shanghai, Poly Real Estate Group shot up 3.9% while rival Gemdale added 2.9%.

Property developer China Vanke added 2.4% after it reported a 22% jump in its first-half profit

In Hong Kong stocks, casino-operator MGM China Holdings fell 2.8% after it reported a quarterly loss. Rival Wynn Macau moved up 0.9%.

Energy stocks were down after crude-oil futures dropped 1.2% in New York. State-owned Cnooc lost 1.3% while subsidiary firm PetroChina was down 1.1%. Asia's largest refiner Sinopec shed 1%.

In Seoul, index heavyweight Samsung Electronics dropped 2.1% while chip-maker SK Hynix was down 2.7%.

Automaker Kia Motors and part-owner Hyundai Motor shed 3% each after Hyundai failed to reach an agreement with its union workers on Tuesday.