The European Champions Cup and Challenge Cup have been temporarily suspended after the French authorities ruled the participation of Top 14 clubs to be too much of a public health risk.
Leinster beat Ulster 27-5 to claim a third successive Pro14 title in emphatic fashion on Sunday (AEST).
Ulster staged a thrilling late comeback to deny Edinburgh and book a Pro14 final against defending champion Leinster.
The Scarlets face a nervous wait to see if they qualify for the Pro14 play-offs after an impressive 41-20 win over the much-changed Dragons on Sunday (AEST) kept them in contention.
JJ Hanrahan missed a vital conversion as Munster slipped to a 27-25 defeat to Conference A leader Leinster in the Pro14.
Wales international James Davies will miss the rest of the season after Scarlets confirmed he is to undergo surgery on a hip injury.