Wal-Mart has put forward two more independent directors - including the former CFO of its Japanese operations - for nomination to its board.

Gregory Penner, a former Wal-Mart executive and now general partner at Madrone Capital Partners, and will go up for election at the retail giant's AGM in June.

The nomination of Arne Sorenson, CFO of hotel chain Marriott International, will also be put to a vote at the meeting.