(Updates closing prices)

By Jiaxing Li and Junko Fujita

HONG KONG/ TOKYO, April 30 (Reuters) - Japan's Nikkei

share average gained on Wednesday as investors awaited

developments in U.S.-Japan tariff talks, helping the benchmark

to register its first monthly gain since December.

The Nikkei added 0.6% to 36,045.38, its highest

close since March 28. The gain marked the index's fifth straight

rising session, its longest winning streak since last August.

The broader Topix also climbed 0.6% to 2,667.29, a

one-month high.

Sentiment was buoyed after Japan's top trade negotiator,

Ryosei Akazawa, said he aims to make steady progress in tariff

negotiations with the U.S. He travelled to Washington later in

the day to meet his counterparts for a second round of

discussions.

That followed fresh data showing Japan's March factory

output fell more than expected, dragged down by its key motor

vehicle industry as U.S. President Donald Trump's tariff

policies continued to rattle manufacturers.

The benchmark index has now recouped all the losses induced

by the early-April tariff announcements, gaining 1.2% for the

month and ending its first month in the green since December.

Markets have largely restored the calm in recent weeks on

hopes of easing trade tensions. Moving away from U.S. assets

amid the tariff-induced chaos also helped Nikkei's rebound.

"For the Nikkei to climb further, a concrete cue - such as

an agreement between Japan and the U.S. - is needed," said

Shuutarou Yasuda, a market analyst at Tokai Tokyo Intelligence

Laboratory.

The stock that gained the most on Wednesday among the top 30

core Topix names was Sony Group ( SONY ), up 7.1%, after a

report the group is considering spinning off its semiconductor

arm, in a move that would unlock value in the company.

The underperformers were Hitachi ( HTHIF ), down 6.1%,

followed by Toyota Motor ( TM ), which lost 2.1%.

Around the region, MSCI's broadest index of Asia-Pacific

shares outside Japan was up 0.7% on Wednesday.

Elsewhere, the Bank of Japan (BOJ) is widely expected to

leave rates unchanged at its two-day policy meeting that ends on

Thursday.

A weaker yen generally benefits Japanese equities by

boosting the value of exporters' overseas revenues. Last month,

Trump accused Tokyo of pursuing policies to weaken the yen,

arguing that it gave Japan an unfair trade advantage.

(Reporting by Jiaxing Li in Hong Kong and Junko Fujita in

Tokyo; Editing by Sumana Nandy and Mrigank Dhaniwala)