Fiji and Japan look set to be locked out of the Nations Championship until 2026 as World Rugby fights for a compromise to get the controversial global competition over the line.

Rugby's global governing body secured a major victory last month when the world's top 12 nations agreed to enter a period of due diligence on the north-south tournament but the concept continues to run aground on the subject of promotion and relegation between the tier one and two competitions.

Shut out: Japan could be sidelined for the start of the proposed Nations Championship. Credit:AAP

The Herald understands the latest proposal being circulated between the unions proposes the new competition kick off with only the 10 nations in the existing Rugby Championship and Six Nations in 2022 and add 12 teams to the southern hemisphere division from 2026.

That means Japan and Fiji, who between them, have in the past four years beat France, Italy and South Africa, will be shut out of the competition for the first four years.