The 69-time former Scotland international striker struck an agreement with MLS outfit Vancouver Whitecaps on Sunday to terminate his two-year deal early.
But despite reports claiming he is set to seal a return to new League One champions Rangers, Miller told the official Whitecaps website: "It's not been discussed yet."
McCoist has never hidden his desire to re-sign the 34-year-old, who has trained at Murray Park on several occasions during breaks from Canada.
But Miller says he will talk to any club willing to offer him terms.
Asked if England could be his eventual destination, the former Hibernian, Wolves and Cardiff player said: "I would probably doubt whether the chance to go back to the Premiership would come up again but I wouldn't rule out anything else, whether that is abroad, back home or England.
"I'm open to listening to anyone who is interested. But you can't pick and choose your destination.
"There is nothing in place as of yet. What this does is give me six or seven weeks to first have a holiday and then sit down with my agent.
"He can then earn his money and find me a new club for July 1. I wouldn't rule anything out."
Miller joined Whitecaps in June 2012 and scored 13 goals in 45 appearances.
He retired from international duty after scoring for Scotland in their 3-2 friendly defeat to England at Wembley last August.
But Miller is not ready to call time on his club career just yet.
"If you speak to any ex-player, they tell you to play as long as you can because it's the one thing you miss," he explained.
"So realistically I can see myself playing for another three years. Obviously I'm getting older but I feel as fit as I've ever done."