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TOKYO, March 31 (Reuters) - Japan's Nikkei share average

tumbled on Monday to its lowest point in more than six months,

following sharp losses on Wall Street in the previous session,

as investors assessed the risk of imminent U.S. trade tariffs.

As of 0130 GMT, the Nikkei was down 3.5% at

35,810.28. Earlier in the session, the index dropped to

35,574.61, its lowest level since September 11.

The broader Topix fell 3% to 2,671.83.

"Investors' sentiment was weakened as there is so much

uncertainty ahead of the announcement of reciprocal tariffs,"

said Hiroyuki Ueno, chief strategist at Sumitomo Mitsui Trust

Asset Management.

"They were in a risk-off mode and offloaded what they had

bought. But this week is the toughest, and they will start

buying them back once the outlook becomes clear."

U.S. President Donald Trump has promised to unveil a massive

tariff plan on Wednesday, which he has dubbed "Liberation Day."

He has already imposed tariffs on aluminum, steel and autos,

along with increased tariffs on all goods from China.

Trump said on Sunday reciprocal tariffs that he is set to

announce will include all nations, not just a smaller group of

10 to 15 countries with the biggest trade imbalances.

Wall Street stocks ended sharply lower on Friday, with

sell-offs in tech giants such as Amazon and Microsoft, after

U.S. data fuelled fears of weak economic growth and high

inflation as the Trump administration ratchets up tariffs.

In Japan, Uniqlo-brand owner Fast Retailing ( FRCOF )

lost 3.6% while chip-related Tokyo Electron ( TOELF ) and

Advantest ( ADTTF ) slipped 5.7% and 6.2%, respectively.

Shares of Mitsubishi UFJ Financial Group ( MUFG ) and

Sumitomo Mitsui Financial Group ( SMFG ) lost 3.9% and 3.3%,

respectively.

Automakers fell, with Toyota Motor ( TM ) and Honda Motor ( HMC )

losing 2.7% and 3%, respectively.

All of the Tokyo Stock Exchange's 33 industry sub-indexes

fell, with the insurance sector lost 4.6%.

The Nikkei volatility index jumped 5 points to 27.4

to its highest level since March 11.

All but one of 225 components of the Nikkei index fell, with

chipmaker Renesas Electronics ( RNECF ) tanking 8.7%.