South Africa and their fellow participants have committed to playing in the Rugby Championship until at least 2025.
The announcement, made by tournament organisers SANZAAR, effectively ends any immediate prospect of South Africa joining the Six Nations.
The world champion Springboks have been consistently linked with becoming a part of European rugby's blue riband competition.
That speculation will inevitably remain, but the Rugby Championship is set to continue in its current form, being contested by South Africa, New Zealand, Australia and Argentina.
"They (South Africa) did put us on notice they were exploring their options. That was well before Christmas," SANZAAR chief executive Brendan Morris told New Zealand-based outlet 'Stuff'.
"We’ve got a number of international and local broadcast deals that are extended to 2025. There was never any cause for alarm that we were never going to meet those obligations.
"We are coming out of the worst three years in living memory of financial impact.
"Everybody has to do their due diligence in exploring what competitions to be involved in and what provides the best opportunity for the best commercial outcome.
"The Six Nations, World Rugby, in all walks of life people are exploring their business models at the moment."
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