Leinster are also top of the ERC European Rankings, which determine the tiers of the teams who have qualified for European club rugby's premier competition.

They are joined in Tier 1 by three other Heineken Cup winners in Munster, Toulouse and Leicester Tigers. Cardiff Blues and Biarritz Olympique, both former Heineken Cup finalists, complete the top group of six.

Ulster, who reached the quarter-finals this past season, are in Tier 3, while the bottom tier includes the likes of Eric Elwood's Connacht, Italian sides Benetton Treviso and Aironi Rugby and Top 14 finalists Montpellier.

Once the Tier 1 teams have each been allocated a different pool, no side from the same tier will be drawn in the same pool and no pool will have more than one team from the same country with the exception of England, as there are seven English teams.

The draw will launch the countdown to a tournament which will climax at Twickenham Stadium over the weekend of May 19-20, 2012.

2011/12 HEINEKEN CUP DRAW:

TEAMS AND TIERS -

TIER 1: LEINSTER, Toulouse, MUNSTER, Cardiff Blues, Biarritz Olympique, Leicester Tigers

TIER 2: Northampton Saints, Clermont Auvergne, Ospreys, Bath, Harlequins, London Irish

TIER 3: ULSTER, Saracens, Gloucester, Glasgow Warriors, Scarlets, Edinburgh

TIER 4: CONNACHT, Benetton Treviso, Castres Olympique, Montpellier, Racing Metro 92, Aironi Rugby