Scottish clubs have decided not to take part in next season’s British & Irish Cup.
As a result only 20 teams, playing in five pools of four, will play in the 2014/15 competition instead of 24.
The Scottish Rugby Union confirmed its clubs will not participate due to the impact it would have on their own domestic calendar.
The 12 clubs of the Greene King IPA Championship will be joined by four provincial teams from Ireland and four Principality Premiership teams will continue to represent Wales in the competition.
RFU professional rugby director Rob Andrew said: "The revision to the British & Irish Cup structure reflects a desire to bring forward the competition knock-out stages, thereby creating its own window within the season with a fitting and unencumbered climax.
“It allows for less congestion and conflict during the business end of the league season. Unfortunately, despite the best efforts of all participating unions, that requirement could not be accommodated by the SRU, due to the impact it would have on their own domestic calendar. As such, the British & Irish Cup will continue with teams from the remaining three unions next season.
"We would like to thank the SRU for their involvement in the competition since its formation in 2009.
“The British & Irish Cup has produced some thrilling, cross-border rugby rivalry and while we regret the loss of Scottish participation, the organising committee is confident in the high level of competition between the Championship, Welsh and Irish teams and we will continue to explore ways to help grow the competition.”
Leinster lifted the British & Irish Cup last season after beating Leeds Carnegie 44-17 in the final.