Arnold Schwarzenegger's rivalry with Sylvester Stallone was "very helpful" to their careers.

The action stars had animosity towards one another at the height of their success in the 1980s and 90s but admitted having someone they could view as "competition" proved to be a great motivator in their work.

In a joint interview for 'TMZ Presents: Arnold + Sly: Rivals, Friends, Icons', Schwarzengger, 76, said: "There’s no two ways about that: He was very helpful in my career because I had something that I could chase.

"[I was] the one who started this whole thing ... by opening up my mouth, saying stupid things, being competitive."

Stallone, 77, added: "[When Arnie] came along I was like finally, something to motivate me. Because he is, dare I say it, competition, a threat, whatever word you wanna use.

"As soon as I saw him it was like bang, two alphas hitting. If we walked into a party we’d be staring at each other for a few seconds and then ‘I gotta get that guy. He didn’t do anything wrong but he will.’ "

The pair laughed over an incident early in their careers when Stallone threw flowers on his rival at the Golden Globe awards in 1977 when Schwarzenegger received the New Actor of the Year prize for 'Stay Hungry' and his own film 'Rocky' took the prestigious Best Picture accolade.

The 'Terminator' star reflected: "We both won, so there was plenty of room for everybody."

But interviewer Harvey Levin pointed out: "That’s not how I remember it. I thought [Stallone], when Rocky won best picture, you threw a bowl of flowers at him?"

Stallone confirmed: "I absolutely did. He was sitting across from me, and I’m going, ‘He won best newcomer?’ No offense, but 'Rocky' was a pretty good debut. And he’s looking very proud of himself and I didn’t think we were gonna win Best Picture.

"We win, and I lost it.

"I literally went and picked up this entire bouquet of flowers and tossed them straight up in the air, sort of aiming towards his side of the table. And it all comes down, he’s sort of sitting there with the same kind of like ‘okay’. He just threw down the gauntlet kind of a thing, here we go."

Schwarzenegger added: "I remember the incident but that was not yet the point where I said, 'Okay this is now the beginning of a battle.’ It just developed from then on. Now I had to chase him."

The former rivals are now friends and the pair admire one another greatly.

Singling out his pal's "dedication and passion", Schwarzenegger said: "I wish I could be as passionate about things as he is.

"It’s really unbelievable, and it must come from somewhere because he’s a very emotional guy, which I’m not. I’m emotional but not like him. Very different in that way."

The 'Rambo' actor admires the former Governor of California's "rock-steady" persona.

He said: "He’s like a season that doesn’t change. Very organised, very calculated, very thoughtful. I’m not, and he’s right, I’m very emotional and I tend to be swayed and things can upset logic quite often. And that’s when you make mistakes, when your heart overwhelms your brain.

"He’s like a chess player: you don’t know what’s going on but he gets it done. And he really does have a big heart, he does.

"I mean, you wouldn’t think it ‘cause we’re ‘action guys’ but we’re more emotional than a lot of more dramatic actors, trust me. Do not think for a second we’re not hypersensitive. Especially coming from where we came from."