South Africa are set to leave the Rugby Championship and form a seven-team Six Nations after the next World Cup in a move which could radically alter the international landscape of the sport, according to reports.

The Daily Mail has reported that behind-the-scenes negotiations have taken place and there is a "sense of inevitability" that the Springboks will drop out of the Rugby Championship which they currently compete in against Australia, New Zealand and Argentina.

The move would cause huge ructions in the southern hemisphere, leaving the Rugby Championship (consisting of Australia, New Zealand, Argentina and South Africa) in crisis.

One source told the newspaper that "things were falling nicely into place" with South Africa set to take place in Europe's premier competition in 2024.

It is understood that the plan in principle would involve expanding the championship to a seven-team event - rather than South Africa's entry coming at the expense of struggling Italy. That would create pressure on an already congested calendar, but the rewards are regarded as too enticing to ignore.

South Africa has already seen two club sides, the Cheetahs and the Southern Kings, drop out of Super Rugby and join the Pro14, which is contested between teams from Wales, Scotland and Ireland.

And the success of that has encouraged last year's World Cup winners to push forward with the plans, in what would be the latest blow to the Southern Hemisphere's premier tournament.

One of the main reasons for South Africa's desire for change is reportedly the time difference between their homeland and the rest of Europe.

They would only be working on a two-hour time difference to adjust their bodies to, rather than the gruelling demands when they travel to Australia and New Zealand.

Another reason is the large South African community in London and the large number of exiles currently playing professional rugby for European-based clubs.

There will be many profound repercussions. South Africa play in the southern hemisphere's Rugby Championship, along with Australia, New Zealand and Argentina. Their departure would leave a gaping hole, but it may allow for the integration of Japan, whose exploits at their home World Cup have led to demands for them to be accommodated in one of the two regular international competitions.

Negotiations are reportedly still ongoing but with talks over a new broadcast deal for the Six Nations set to begin, the potential addition of South Africa will need to be confirmed sooner rather than later.