South African sides Southern Kings and Cheetahs will join an expanded Pro14 from September, organisers confirm.
Garry Ringrose will miss Ireland's November Tests as he faces four to five months out of action after surgery on a shoulder injury.
Ulster will play Wasps, La Rochelle and Harlequins in Pool One of next season's European Champions Cup.
Leo Cullen is given a two-year contract extension as head coach of Leinster with Stuart Lancaster also retained in the role of senior coach.
Audio & Video
British and Irish Lions head coach Warren Gatland praises Jared Payne and Rob Henshaw after selecting the Ireland pair in the team to face the Blues on Wednesday.
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