TOKYO, Sept 22 (Reuters) - Japan's Nikkei share average sank to an almost four-week trough on Friday, tracking sharp declines on Wall Street amid worries about a more hawkish Federal Reserve.

The Bank of Japan is due to announce its latest policy decision around midday in Tokyo, adding to nerves after Governor Kazuo Ueda hinted in a newspaper interview earlier this month that an end to negative interest rates could come as early as this year.

The Nikkei fell as low as 32,154.53 for the first time since Aug. 28 and was 0.89% lower at 32,277.18 as of 0140 GMT, extending its retreat from last week's 2-1/2-month peak at 33,634.31.

Of the Nikkei's 225 components, 186 fell, 38 gained and one traded flat.

The broader Topix declined 0.64%.

"The narrative regarding BOJ policy has shifted meaningfully over the past fortnight ... putting an end to negative rates at the forefront of market participants' minds," Kyle Rodda, senior financial market analyst at, wrote in a note.

"The markets will be searching for a change in language, however subtle, about the prospect of rate rises."

Ueda's news conference is scheduled for half an hour after the stock market close, at 0630 GMT.

The BOJ has been a global outlier in sticking with ultra-easy stimulus as the Fed and most other major peers adopt a mantra of higher rates for longer to tackle stubborn inflation.

Worries about tighter financial conditions saw all three of Wall Street's major indexes slide more than 1% overnight.

Even in Japan, data earlier on Friday showed core inflation sticking above the BOJ's 2% target for a 17th straight month.

Noteworthy decliners on Friday included chipmaking-equipment manufacturer Tokyo Electron, which fell 1.9% to make the heavily weighted stock the biggest drag on the Nikkei.

Startup investor SoftBank Group sank 1.84% after its chip designer Arm Holdings dipped below its IPO price overnight. (Reporting by Kevin Buckland; Editing by Subhranshu Sahu)