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 eight percent. Broadcaster NHK reported late 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 percent by the break of trade in Tokyo, having earlier rocketed 10 percent. The 7-Eleven franchise began in the United States, but it 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. — Agence France-Presse