TOKYO (Kyodo) -- Tokyo stocks snapped a four-day winning streak Friday, as investors moved to lock in gains, while defense-related issues fell due to growing uncertainty over the timing of an income tax hike to fund a defense spending increase.

The 225-issue Nikkei Stock Average ended down 378.70 points, or 0.95 percent, from Thursday at 39,470.44. The broader Topix index finished 26.47 points, or 0.95 percent, lower at 2,746.56.

On the top-tier Prime Market, decliners were led by pharmaceutical, machinery and electric appliance shares.

The U.S. dollar remained firm, briefly topping the 153 yen line in Tokyo for the first time in two weeks, as Japanese importers bought the U.S. currency for settlement purposes at the end of the week, dealers said

At 5 p.m., the dollar fetched 152.79-81 yen compared with 152.60-70 yen in New York and 152.57-58 yen in Tokyo at 5 p.m. Thursday.

The euro was quoted at $1.0459-0460 and 159.81-85 yen against $1.0462-0472 and 159.69-79 yen in New York and $1.0516-0517 and 160.45-49 yen in Tokyo late Thursday afternoon.

The yield on the benchmark 10-year Japanese government bond fell 0.010 percentage point from Thursday's close to 1.035 percent. The debt was bought on expectations that the Bank of Japan will forgo raising interest rates later this month.

On the stock market, investors locked in gains after the Nikkei index added more than 750 points over the past four days and briefly exceeded the 40,000 threshold Thursday for the first time in two months.

Defense-related shares fell after Japan's ruling parties agreed to put off a decision on when to raise income tax to help fund a planned defense spending increase, although reports said earlier this week that a hike was planned to take place from January 2027.

"Today's news regarding tax hikes for defense funding was a reversal of the earlier reports, prompting investors to unload shares after recent rises," said Toshikazu Horiuchi, equity strategist at IwaiCosmo Securities Co.

China-related shares were sold, as investors were disappointed by a lack of details about China's economy-boosting steps after Beijing signaled earlier this week it would implement stronger stimulus measures next year, he said.