Japanese c-store operator 7-Eleven has launched a $1.2bn cash tender offer to buy the 27.3% stake it does not already own in its US subsidiary 7-Eleven US.

7-Eleven Japan, which operates more than 10,000 stores, already holds a 72.7% stake in 7-Eleven US, and has offered $32.50 a share in cash for the remaining shares.

The group said that it would advise shareholders on or before September 19 on the offer.