World Rugby vice-chairman Agustin Pichot has challenged Sanzaar to invite Japan to join the Rugby Championship.
The Argentinian would also like to see Georgia enter the Six Nations as part of his plan for World Rugby to grow and develop smaller nations.
Pichot's call to see the Brave Blossoms in the Rugby Championship, alongside the All Blacks, South Africa, Australia and Argentina, comes as the Sunwolves ended their second Super Rugby campaign for a stunning win over the Blues in Tokyo.
"'I would love to see the Six Nations open up to Georgia. I would also challenge SANZAAR to open up to Japan and the Americas Championship to countries to like Mexico. Those are the type of things that motivates me to be a suit; the growth of the women's game, establishing rugby in China," Pichot told the Telegraph.
Japan are currently ranked 11th in the world and produced one of the shocks of the last World Cup when they defeated the Springboks in Brighton during pool play.
Pichot, a former Pumas skipper, says World Rugby have to continue to grow the sport.
"If we do everything for money then you can play a World Cup every year with just 10 countries. Just have a few club sides around the world who play each other all the time. Sell it to Sky or to BT Sport and Canal Plus. Straight away you would have 80 per cent of the revenue of World Rugby. Keep taking players out of Argentina and Fiji and do it that way. Maybe it is more profitable, but I don't want to do it that way.
"What are we here for? I am not naive. I understand we have to make sure the business grows but we cannot lose what rugby stands for."