TOKYO (Kyodo) -- Tokyo stocks ended lower Wednesday for the fourth straight trading day, amid caution ahead of the outcome of a U.S. Federal Reserve monetary policy meeting, while automaker shares mostly rose after reports of merger talks between Honda Motor Co. and Nissan Motor Co.

The 225-issue Nikkei Stock Average ended down 282.97 points, or 0.72 percent, from Tuesday at 39,081.71. The broader Topix index finished 8.33 points, or 0.31 percent, lower at 2,719.87.

On the top-tier Prime Market, decliners were led by retail, service, and information and communication issues.

The U.S. dollar was slightly weaker in the lower 153 yen range in Tokyo as investors adjusted their positions before the Fed announces the results of its two-day policy meeting later Wednesday, dealers said.

At 5 p.m., the dollar fetched 153.57-59 yen compared with 153.41-51 yen in New York and 154.06-08 yen in Tokyo at 5 p.m. Tuesday.

The euro was quoted at $1.0496-0498 and 161.19-23 yen against $1.0487-0497 and 161.02-12 yen in New York and $1.0497-0498 and 161.72-76 yen in Tokyo late Tuesday afternoon.

The yield on the benchmark 10-year Japanese government bond fell 0.015 percentage point from Tuesday's close to 1.060 percent as the debt was bought on speculation that the Bank of Japan will forgo an interest rate hike at its two-day policy meeting through Thursday.

On the stock market, investors refrained from buying actively amid a wait-and-see mood, with the market focusing on the Fed's pace of expected interest rate cuts while the central bank is widely seen to reduce rates by 0.25 percentage point, brokers said.

Bucking the trend, many automakers attracted buying after reports that Nissan and Honda are arranging merger talks amid fierce global competition in the electric vehicle sector.

The reports fueled hopes that Toyota Motor Corp. and other automakers could also move toward merging with others, said Seiichi Suzuki, chief equity market analyst at the Tokai Tokyo Intelligence Laboratory Co.

"But such speculative buying is unlikely to continue tomorrow, as market participants are likely to rethink that a similar move will not emerge for some time," he added.

Trading of Nissan shares was briefly halted before going on to end the day up 23.7 percent at 417.6 yen, while Honda dropped 3.0 percent to 1,244.5 yen.