It means that the South African teams will be able to qualify for European games.
Tournament organisers have confirmed that the new 16-team PRO rugby competition will be called the United Rugby Championship.
South African clubs the Sharks, Stormers, Lions and Bulls will enter the league next season alongside the teams who competed in last year's Guinness PRO14.
It will see the return of a single-standing table with quarter-finals, semi-finals and a grand final at the end of the regular campaign.
Under the agreement, the South African sides will be eligible to qualify for European competitions.
Here's an explainer of how it will all work:
Everything you need to know ⬇️
— PRO14 RUGBY (@PRO14Official) June 15, 2021
One league table to rule them all... and regional tables to hype the rivalries!#URC pic.twitter.com/xkqeCBOEbf
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