TOKYO: Tokyo's benchmark Nikkei index closed down for a fourth consecutive session on Thursday as worries about a potential US government shutdown overwhelmed support from a cheaper yen.

The Nikkei 225 index fell 0.31 percent, or 91.63 points, to 29,452.66, while the broader Topix index lost 0.40 percent, or 8.13 points, to 2,030.16.

Investors remain cautious ahead of the deadline for the US debt ceiling bill later in the day, fearing a potential government shutdown, analysts said.

"They are expected to strike a deal on the debt ceiling in the end, but investors are still cautious," said Toshikazu Horiuchi of IwaiCosmo Securities.

Tokyo's Nikkei opens down 2% on global market jitters

Democrats announced that the US Senate will vote Thursday on legislation to fund federal agencies, which is likely to avert the shutdown.

The dollar fetched 111.92 yen in Asian afternoon trade, slightly down from 111.98 yen in New York but still up from 111.43 yen in late Tokyo hours on Wednesday.

A cheaper yen is good for Japanese exporters as it makes their products more competitive abroad while inflating profits when repatriated.

There was no strong reaction to Japan's ruling Liberal Democratic Party choosing Fumio Kishida as their new leader and the country's next prime minister.

Seen as a safe pair of hands likely to continue existing government policy, Kishida will be approved as prime minister by parliament on October 4.

"The market largely welcomes Kishida," while expecting his promised stimulus measures and awaiting the lineup of his cabinet members, Horiuchi said.

In Tokyo, tech shares faced more selling pressure after the Nasdaq index slipped in New York.

Tokyo Electron, which makes equipment to build chips, lost 2.60 percent to 49,670 yen as Advantest, a producer of chip-testing tools, fell 1.76 percent to 10,030 yen.

SoftBank Group dropped 3.03 percent to 6,480 yen but Uniqlo casual wear operator Fast Retailing jumped 4.29 percent to 82,480 yen.