TOKYO, Nov. 22 (Xinhua) -- Japan's benchmark Nikkei stock index closed higher Tuesday, as the yen's weakness against the U.S. dollar gave exporters a boost, while investors bought back oversold issues to cover short positions ahead of a national holiday on Wednesday.

The 225-issue Nikkei Stock Average gained 170.95 points, or 0.61 percent, from Monday to close the day at 28,115.74.

The broader Topix index, meanwhile, added 22.18 points, or 1.12 percent, to finish at 1,994.75.

Market analysts said amid a lack of significant cues other than the yen's decline against the U.S. dollar, along with exporter issues finding favor, investors opted to buy back issues at favorable valuations.

"There were no specific market-moving cues but investors liked the yen's weakness. Investors probably bought back stocks to cover their short positions ahead of a market holiday tomorrow as the yen may weaken further after comments from the Federal Reserve," Yutaka Miura, senior technical analyst at Mizuho Securities Co., was quoted as saying.

"But U.S. equities could fall if the markets find any hawkish remarks from Fed officials, which may trigger a sell-off in Japanese futures on Friday," Miura said.

The possible hawkish remarks could come from the Fed's latest meeting, the minutes of which will be released this week, said local analysts.

As for the yen's further weakening, exchange strategists said this could be the case ahead of national holidays both in Japan and the United States.

"The dollar may rise further to the 143 yen level ahead of a national holiday in Japan on Wednesday and Thanksgiving holidays in the United States this week," Yukio Ishizuki, a senior foreign exchange strategist at Daiwa Securities Co., was quoted as saying.

On the Prime Market, electric power and gas, pharmaceutical, and transportation equipment-linked issues comprised those that gained the most.

Exporters gained on the yen's retreat as profits made overseas are augmented when repatriated and price-competitiveness enhanced in global markets, investment analysts said.

Among these, automakers advanced, with Toyota Motor accelerating 2.3 percent, while Mazda Motor ended 1.2 percent higher.

Shionogi & Co. climbed 2.8 percent, following reports that Japan's health ministry may soon approve the pharmaceutical firm's new COVID-19 oral treatment.

Chipmakers ended mixed, with Nikkei heavyweight Tokyo Electron bouncing back to close 0.1 percent higher, while fellow heavyweight Advantest dropped 1.4 percent.

Issues that rose outpaced those that fell by 1,467 to 325 on the Prime Market, while 44 ended the day unchanged.

On Tuesday, 1,204.28 million shares changed hands, dropping from Monday's volume of 965.30 million shares.

The turnover on the second trading day of the week came to 2,923.18 billion yen (20.69 billion U.S. dollars).