It's one of the most iconic lines in film history - but it almost didn't pan out that way.

'I'll be back' from 'The Terminator' is a line that has become synonymous with Arnold Schwarzenegger and his most famous character - but as the Austrian actor revealed in his new Netflix documentary, he wanted to phrase it differently.

Schwarzenegger recalled how he and director James Cameron clashed over the line, as the actor thought that 'I'll be back' was too casual for a cyborg.

Cameron explained what happened. "Sometime in the middle of the shoot, we’re doing this police station scene. The line is, ‘I’ll come back.’ It wasn’t meant to be like a big moment at all," he said. "It was literally meant to be, on its face: ‘No problem, I’ll come back.’ For some reason, Arnold didn’t say ‘I’ll come back.’ I said, ‘Well, just say “I’ll be back.” Keep it simple.'"

However, Schwarzenegger thought 'I'll be back' sounded "funny" and wanted to say "I will be back" instead - but recalled how Cameron asked him "Are you the writer?'". When he replied no, Cameron told him "Well, don’t tell me how to fucking write".

The rest, as the say, is history.

'Arnold' is streaming on Netflix now.