It was recently announced that all six Star Wars films are to be released in cinemas in 3D from 2012. Series creator Lucas had previously cited the success of Cameron's Avatar as a key factor in persuading him to press ahead with the 3D conversion.
Cameron told the New York Times that enough time has passed since the original release of Star Wars for the project to be worthwhile.
On the franchise's 3D release, Cameron said: "George has been talking about this for a long time and it's finally coming to fruition. I've been encouraging him to do that for years. He did hang back for a while. I think he was waiting for there to be a wide enough install base in movie theatres, and now we're looking at the roll-out of 3D television.
"I think he's timed it wisely to a point where he can do the theatrical re-release and then roll right into a 3D DVD re-release. You don't want to create a glut of your own product. He had only just, a couple of years ago, finished his whole epic cycle of six films."
Cameron went on to clarify earlier comments in which he criticised the "stupid" decision to retro-fit 2D movies with 3D effects, having used Clash Of The Titans as a cautionary example.
He added: "I think the true and correct use of the conversion technology is for movies that are already done and are already beloved films. I want to do it with Titanic, maybe I'll go back to T2, I don't know.
"Steven [Spielberg] could do it on some of his films that we'd all, I'm sure, love to see in 3D. But it has to be done right, and it has to be done with the blessing and the supervision of the filmmaker."