Defending European and Premiership champions Saracens will meet two-time winners Munster, French giants Racing 92 and the only Welsh side in the competition Ospreys in the pool stages of next season’s Champions Cup.
They all meet in a tough Pool Four, while Pro14 winners Leinster face Lyon, Northampton and Benetton in Pool One.
Top 14 winners Toulouse face Gloucester, Connacht and Montpellier in Pool Five, while Premiership rivals Bath and Harlequins contest Pool Three with Clermont Auvergne and Ulster.
Elsewhere, Premiership runners-up Exeter come up against with Glasgow – the former club of Exeter’s new signing Stuart Hogg – Sale Sharks and La Rochelle.
In the Challenge Cup, Leicester will face Cardiff Blues, Pau and Calvisano as their pool stage opponents, the Tigers having failed to qualify for the Champions Cup following a dismal Premiership season.
Wasps were grouped with Edinburgh, Bordeaux-Begles and Agen, while newly-promoted Premiership club London Irish will tackle a testing pool that also features Scarlets, Toulon and Bayonne.
The first round of European games take place on 15-17 November.
|European Champions Cup final wins|
|4: Toulouse, Leinster|
|3: Saracens, Toulon|
|2: Leicester, Munster, Wasps|
|1: Brive, Northampton, Ulster, Bath|
Champions Cup 2019-20 draw
Pool One: Leinster, Lyon, Northampton Saints, Benetton
Pool Two: Exeter Chiefs, Glasgow Warriors, La Rochelle, Sale Sharks
Pool Three: ASM Clermont Auvergne, Ulster Rugby, Harlequins, Bath
Pool Four: Saracens, Munster, Racing 92, Ospreys
Pool Five: Toulouse, Gloucester, Connacht, Montpellier
Challenge Cup 2019-20 draw
Pool One: Castres Olympique, Worcester Warriors, Dragons, Enisei-STM
Pool Two: Scarlets, RC Toulon, London Irish, Bayonne
Pool Three: Wasps, Edinburgh Rugby, Bordeaux-Begles, Agen
Pool Four: Stade Francais Paris, Bristol Bears, Zebre Rugby Club, Brive
Pool Five: Cardiff Blues, Leicester Tigers, Pau, Rugby Calvisano