Weiland was dismissed earlier this year (13) and he is now embroiled in a bitter legal battle with his former friends, who have sued him over allegations he sabotaged the group's recent 20th anniversary tour by turning up late for performances and missing promotional gigs.
DeLeo has now opened up about the tensions in the group which led to Weiland's exit, insisting they needed to move forward without him.
He tells Rolling Stone, "It was a very difficult decision to terminate the face of your band. There are many paths to the history of certain bands and each one is a little different, but it all kind of turns out the same at the end. But it was a very difficult decision to do that. That's as big as it gets. But we really didn't have any other choice... (We) have been saddled by someone for a long time. We've always looked out for Scott's best interests and tried to be a great friend to someone who really didn't care to be friends with us...
"And I don't think we had any other choice... (We) would rather move ahead. I want to have f**king fun, man, making music. I have the complete luxury of making music for a living. If I'm around people that don't f**king get that, then I want to be around people who get that."
Stone Temple Pilots are now working with Linkin Park's Chester Bennington as their frontman, and DeLeo admits he feels grateful to the singer's bandmates for letting him take up the post.
He adds, "I feel very humbled by the fact the guys in Linkin Park are cool with this. All these guys are great dudes. It's not about music - it's about the humanity of it. They're the kind of human beings you want to be around at this point in life."
Bennington concludes, "I really respect the decision these guys have made. I also understand how incredibly difficult having that conversation would be... (But) this is their life. This is how they're gonna pay their bills and put their kids through college, this is how they're gonna want to spend the rest of their lives."