South African sides Southern Kings and Cheetahs will join an expanded Pro14 from September, organisers confirm.
Edinburgh and London Irish are to meet holders Stade Francais in the Pool stage of next season's European Challenge Cup.
Northampton will take on Stade Francais for a place in next season's European Champions Cup after beating Connacht in the play-off semi-final.
Munster finish top of the Pro12 table by running in seven tries as they beat Irish interprovincials Connacht.
Audio & Video
Highlights as Pro12 champions Connacht beat Newport Gwent Dragons in Galway.
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