Tyson, who has not fought since a first-round knockout of Clifford Etienne in February 2003, announced on Tuesday that a July 30 date had been set for the bout in Louisville, Kentucky.
"I'm not here to be a tough guy, I'll be a tough guy on July 30," Tyson, told a media conference to announce the fight. "When I make my mind up, that's when I fight. I have been foolish not to fight."
He added: "I have not done a thing that has benefited me. You guys (the media) will be the judgement of whether I have the eye of the tiger or not."
The fight is the first in a plan developed by Tyson's lawyers to pay off his massive debts.
The self-proclaimed "baddest man on the planet," Tyson has amassed over $300 million in purses throughout a turbulent career but is now believed to owe $38 million to various creditors, including the Internal Revenue Service and his ex-wife Monica Turner.
According to reports, Tyson is now penniless and was quoted earlier this month as saying: "For two years I have been a bum, truly a bum in the streets. I've got nowhere to live.
"I've been crashing with friends, literally sleeping in shelters."
Once regarded as the most feared fighter of his generation, Tyson's fierce aura and savage skills have eroded through inactivity, fighting just twice in the last three years.
In fact, Tyson has fought just eight times since losing a re-match with Evander Holyfield in 1997, compiling a record of five wins, one loss and two no contests.
The defeat was a brutal beating at the hands of Lennox Lewis, who sent Tyson to the canvas with a thundering right in the eighth round in Memphis in June 2002.
But Tyson (50-4, 44 knockouts), who turns 38 on Wednesday, will still be expected to make a winning return to the ring against the journeyman Williams (31-3, 26 KOs).
A victory over the Londoner also set Tyson on a path to more big paydays and slow the downward spiral his career has been in since spending three years in prison after being convicted of rape in 1992.
He was also banned from boxing in 1997 after biting off part of Holyfield's ear in a title bout.
Tyson said: "I may have a chequered past, which we all have, some more publicized than others. But I think I've grown since then and I deserve another chance to prove that my chequered past can be swept away."
