Japanese beverages firm Kirin Holdings is in talks to invest $70 million in Indian craft beer maker Bira, sources have said, doubling down on the fast-expanding South Asian market at a time when it is facing pressure on growth at home.

Kirin, which first invested $30 million in Bira for an under 10% stake last year, is set to pump in the additional funds at an equity valuation of $450 million, the sources said. Negotiations between the Japanese company and Bira's owners are in the final stage, one of the sources said.

The latest deal talks come as Japan's major drink makers are facing a steady decline in revenue from alcohol sales as the domestic population shrinks and younger people drink less than in previous decades, forcing the companies to expand overseas or foray into new markets.