It is the second biggest acquisition by a Japanese brewer on record, behind brewer and distiller Suntory Holdings Ltd's near $14 billion purchase of Beam in January 2014.
Asahi shares fell as much as 6.4 percent after the report before closing down 4.6 percent, with market participants pointing to investor nerves about how the deal would be funded.
Asahi's statement did not say how the deal would be funded. As of September, Asahi had $471 million in cash on its balance sheet, according to Thomson Reuters data.
"If funding is by a large amount of cash, it reduces the probability of ROE (return on equity) activity," said Gavin Parry, managing director of Parry International Trading in Hong Kong. "Without details on funding, you have to assume it would impact cashflow."
Not including the potential Asahi deal, Japanese companies have spent $77.6 billion on outbound mergers and acquisitions, Thomson Reuters data shows, as they seek to counter bleak prospects, including deflation, weak consumer spending and a falling population, at home.
The Asahi deal pushes this year's figure close to the record $87 billion Japan Inc spent on overseas M&A in 2015.
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