He said it on air multiple times.
Here is a full print interview and the excerpt of him comments below
NPR Choice page
From Aug 2010
COX: Have you communicated with him personally?
Prof. WEST: Well, I'll tell you, I had not talked to my dear brother since the Martin Luther King gathering in South Carolina, and very briefly Super Tuesday. But he did come and make a beeline to me after his speech on I think it was Thursday morning in Washington, D.C. I hadn't seen him for two and a half weeks, and he made a beeline to me, though, brother, and he was deeply upset. He talked to me like I was a Cub Scout, and he was a pack master, you know what I mean?
I said, well, my mother and father raised me right. I respect my dear brother, but I don't like to be demeaned and humiliated in that way, and I didn't get a chance to respond to him. And I hope maybe at some time we can. But it was very, it was a very ugly kind of moment, it seems to me, and that disturbs me because then it raises the question for me: Does he have a double standard for black critics as opposed to white critics?
Frank Rich, Paul Krugman, Maureen Dowd, a whole host of brilliant, courageous critics say all kinds of things, and he treats them with respect. They get invited to the White House. I say the same thing, he talks to me like I'm a Cub Scout.
I dont like that. It raises the question, too, is, you know, how many black folk need to be sacrificed for his campaign and his governance...
==============
President Obama welcomed and gave access to several Black intellectuals and leaders, so Dr. West was forced to drop the "he sacrifices/drops Blacks who criticize him" angle.
Remember Obama was inaugurated in Jan 2009, this article is from a year and a half later.
I love and respect Dr. West, but he openly mentioned the snub multiple times, and that was the main reason he went in on Obama.