Japanese retail giant Seven & i Holdings has rejected a takeover bid from a major Canadian convenience store operator, saying its offer "grossly undervalues" the company.

The owner of the 7-Eleven convenience store chain released a letter it sent on Friday to Alimentation Couche-Tard, which runs stores and gas stations around the world.

The letter said the Seven & i board had decided the proposal was not in the best interests of the company's shareholders, based on the recommendation of an independent committee of outside directors.

The letter disclosed that the Canadian company had offered 14.86 dollars per share, valuing the bid at about 39 billion dollars.

Seven & i noted that even if the price were raised, a merger of the top two convenience store operators in the United States would face significant regulatory hurdles under US competition law.

Seven & i has not closed the door completely. It said it remains open to discussing any offer that fully recognizes the company's intrinsic value.

The Canadian firm's chief executive said on Thursday before the letter was sent that the company was confident in its ability to finance and complete the acquisition.