Including two South African sides is not easy to sell, but Pro12 organisers say it has to be made to work amid financial pressures, says Tom English.
Scottish Rugby Union
Pro12 derbies would be protected if the league splits into two conferences after the arrival of Cheetahs and Southern Kings.
The Pro12 has agreed a deal to expand next season to include South African sides Cheetahs and Southern Kings, BBC Scotland understands.
South African sides Southern Kings and Cheetahs are expected to join the Pro12 for next season.
Audio & Video
Scotland debutant Nick Grigg, the Glasgow Warriors centre, talks to BBC Scotland's Tom English about earning his first international cap.
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