Seven & i, owner of the world’s biggest convenience store chain, earlier this year rejected an offer of nearly US$40 billion from Canadian rival Alimentation Couche-Tard (ACT).

ACT has since sweetened its offer, which if completed would be the biggest foreign takeover of a Japanese company, creating a convenience store behemoth with some 100,000 outlets.

Last week Seven & i said it was studying a counter-offer from its vice president Junro Ito, the founder’s son, and his company Ito-Kogyo, which already has a stake of around 8%.

Broadcaster NHK reported late on Tuesday that they were seeking to raise more than eight trillion yen (US$50 billion) from banks and to complete the takeover this fiscal year, which ends on March 31.

Seven & i told AFP that no official announcement had been made. The firm’s shares were up 8.4% by the break of trade in Tokyo, having earlier rocketed 10%.

The 7-Eleven franchise began in the US, but has been wholly owned by Seven & i since 2005.

Around a quarter of 7-Eleven stores are in Japan, where they are a cherished one-stop shop for everything from rice balls to concert tickets.

Couche-Tard, which began with one store in Canada’s city of Laval in 1980, now runs nearly 17,000 convenience outlets worldwide.