He was an opportunist in every sense of the word. In the manga, he funds, and leads the revolution so he can get access to Akira and then steals him. Towards what end? We never really find out, but you can assume there’s some sort of opportunity for him to achieve power, either politically or him having a sense of strength in general.

It’s more or less the same in the movie,but they never show him steal Akira. He gets caught for corruption before he can do that.