The Rossoneri official stressed that the upcoming clash will not be easy and noted that Massimiliano Allegri deserved a new contract after an impressive first season at the club
The Serie A holders are eight points above their local rivals going into the grudge match but, despite the big difference between the two clubs in the table, Galliani is anticipating a difficult game for his team.
"On Sunday we will play a very important match against a very strong side," he told Milan Channel.
"Inter have a good team and they will reach the top places."
Galliani went on to hail the work of Milan coach Massimiliano Allegri, who signed a contract extension until 2014 on Friday.
"I remember saying that he was the right man for the job and that he had done so much in his first year," he added.
"He deserved a new contract for all he has done. If there were talks about money, it was because were are in a financial crisis, but then we reached an agreement."
The crunch match gets under way at San Siro at 20.45CET.
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