A man looks at his watch as he passes an electronic board displaying a graph of currency rates outside a brokerage in Tokyo.

Tokyo stocks surged on Thursday as the benchmark Nikkei 225 index closed at a fresh eight-month high, with a tumbling yen boosting exporter shares as investors bet on central bank easing.

The Nikkei jumped 1.68 percent, or 161.27 points, to 9,742.73, its highest finish since early April, in heavy trading on the Tokyo Stock Exchange.

The Topix index of all first-section shares gained 1.00 percent, or 7.92 points, at 799.21, near an eight-month high.

On currency markets, the safe-haven yen sank to multi-month lows against the dollar and yen on rising risk sentiment ahead of weekend elections in Japan widely expected to return the Liberal Democratic Party (LDP) to power.

Shinzo Abe, the LDP's leader, has vowed to pressure the Bank of Japan (BoJ) for more aggressive easing as the world's third-largest economy slips into recession, with his comments helping pushing down the Japanese unit.

Major exporters gained on the yen's dip Thursday. A strong currency makes Japanese manufacturers less competitive overseas while shrinking their repatriated foreign income.

“The opposition Liberal Democratic Party looks poised for a big win Sunday, so if it can move on its BOJ/aggressive easing pledge, the dollar stands to gain a lot more - perhaps to the 85 yen level short term,” said Mitsushige Akino, chief fund manager at Ichiyoshi Investment Management.

“If that happens, automakers especially will be in for a great deal of bidding.”

In Tokyo trade, Toyota rose 1.12 percent at 3,600 yen, Mazda Motor surged 4.41 percent to 142 yen, Sony gained 6.36 percent to 886 yen and Nikon jumped 6.42 percent to 2,401 yen.

Panasonic gained 7.84 percent to 481 yen on reports it will boost its overseas production of solar panels with the struggling electronics giants to start up its new Malaysian solar-panel factory on Thursday.

After a two-day meeting, the policy committee of the US central bank said Wednesday it would replace its “Operation Twist” bond swapping programme with $45 billion a month in straight bond buys, on an open-ended basis.

That comes on top of the $40 billion a month purchasing announced earlier.

The Fed move has stoked expectations of further easing by the European Central Bank and Japanese policymakers on the back of fears over slowing in the global economy, dealers said.

“The bottom line is that (the Fed) will continue its aggressive steps to foster economic growth,” Hiroichi Nishi, general manager of equities at SMBC Nikko Securities, told Dow Jones Newswires. - Sapa-AFP