Tokyo's benchmark Nikkei index rose to a 27-year high on Monday, boosted by a weak yen and a breakthrough in trade talks between the United States and Canada.
The Nikkei 225 index gained 0.52% to close at 24 245.76 - the highest since November 1991 when Japan Inc was closing the final chapter of the nation's speculative "bubble" economy.
"Reaching a 27-year high is symbolic but still a stop on the road to further gains," Toshikazu Horiuchi, a broker at IwaiCosmo Securities, told AFP.
The Topix index edged up 0.04% to 1 817.96.
The increases were driven in part by a rise in the yen to ¥113.95 in afternoon trade, from ¥113.67 late on Friday in New York.
"The ¥113 level is definitely positive for Japanese exporters," Hikaru Sato, senior technical analyst at Daiwa Securities, told AFP.
And analysts said a breakthrough in a trade deal renegotiation between Canada and the US also boosted the market.
The deal, which includes Mexico, came after more than a year of talks to revamp the North American Free Trade Agreement that President Donald Trump has labelled a disaster.
"While the market maintained its strong momentum, it would be no surprise to see investors cash in on the recent gains at any time," Sato said.
Investors largely ignored a decline in business sentiment among large Japanese manufacturers announced by the Bank of Japan shortly before the market opened.
In Tokyo, Panasonic jumped 0.90% to ¥1 335.5 with Nintendo up 1.39% at ¥42 040.
Automakers declined as investors locked in profits on last week's jump following news that the US will not impose additional tariffs on Japanese-made cars.
Toyota lost 0.49% to ¥7 060 with Honda down 0.14% at ¥3 434.
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