The 48-year-old Briton, who was the last undisputed heavyweight champion of the world, was offered $50m (£31.3m) by promoters to fight again as he watched Wladimir Klitschko’s world title defence Alexander Povetkin at the weekend.
That figure was on his mind the last time he considered a return to the ring, but he would now expect double that.
"I said at the time that it will take $50million to get me out of my pyjamas but now I have to consider the value of my legacy of having retired as undisputed champion," was quoted as saying by the Mail.
"That will cost them $100million."
Lewis is certainly talking a good fight at the moment after having told the Telegraph that he would still be able to knock out Tyson Fury. Fury then launched into a Twitter tirade over the claim, but Lewis appears ready to back his words up in the ring, telling the Mail that he would return to professional boxing – for the right money.
"($100m) is my price tag and it is under discussion," Lewis said.
"I have told them I can be ready in six months and I am in provisional training.
"I am already under 300lb (around 50lb shy of his fighting weight)."
The 6’5” Lewis retired in 2004 after a 16-year professional career that was preceded by five years as an amateur, which saw him win Olympic gold at Seoul in 1988.
Lewis quit the sport after retaining multiple world titles against Vitali Klitschko in June 2003, initially promising to fight on but later backtracking. His record stands at 42-2-1, and he is widely regarded as the last great heavyweight.
The Klitschko brothers have since gone on to dominate the division, which has declined in popularity due to a relative lack of talent, and the emergence of Mixed Martial Arts.
Of the two Klitschko brothers, Lewis said he would prefer to fight Wladimir, having already proved himself against Vitali.
"I beat Vitali so I would like to fight the other brother but we’ll see how it works out. I want to bring back the Sweet Science to heavyweight boxing," he said.
Lewis was ringside for Wladimir’s victory over Povetkin, who was knocked down four times, but having watched the fight at close quarters, he left rather underwhelmed.
"In a way this fight confirmed my disappointment with the state of heavyweight boxing right now," he said. "The best I could find to challenge Wladimir was a kid who is not fully developed either physically or in terms of experience.
"People paid a lot of money in expectation of a great fight but Povetkin was not properly prepared for the most important fight of his career.
"Wladimir should have gone for the knockout after putting him down four times but I think he missed having [the late] Manny Steward in his corner. Manny would have told him what he told me when I fought Vitali - to go in and finish him.
"I suspect Wladimir had a problem with his right hand because as the fight went on he didn’t use it that often. But having said that he showed great movement, was very light on his feet and was never in danger of losing."