Schu does not have key Ferrari role – boss
"He came to a few races last year, he came at the beginning of this season and he will come again," the Italian is quoted as telling reporters at Sakhir by the German SID news agency.
"But he does not have a responsible role because he does not have the time to be at Maranello," Montezemolo added.
Schumacher, 40, was harshly criticized for his role in strategy blunders when he stood on the Ferrari pitwall in Australia and Malaysia.
Montezemolo said: "He gives ideas and proposals as an advisor — no more and no less."
He said he once asked the German to take over from Jean Todt as team principal, but Schumacher emphatically answered "no!".
"Michael has a good mentality, but I understand that his life is now something else. So I asked him to come to a few races and support us," said Montezemolo.
Meanwhile, when asked to summaries F1's new pecking order that has left Ferrari ninth in the constructors' championship, Montezemolo hit out at "very badly written rules".