English and French rugby clubs announced last month that they planned to set up their own competition after running out of patience with stalled negotiations over the future of the Heineken Cup.
Europe's two most powerful unions are frustrated by what they see as a qualifying system unfairly weighted in favour of Irish, Welsh and Scottish clubs and want a greater share of income from the tournament.
In a statement ERC said the 80,000-capacity San Siro would stage the 20th edition of the European club rugby final.
"We are in a difficult period for European club rugby and I hope that a solution can be found and then we can look forward to 2015 and a celebration of 20 years of European club rugby in Milan. It would be a shame if Italian rugby lost such a major opportunity to promote the game in their country," ERC chairman Jean-Pierre Lux said.