"I was offered billions of rupees in betting. There was a briefcase full of money placed on the table before me in Johannesburg," Akhtar said in television interviews broadcast late on Wednesday.
"I was never tempted yet I am punished for doing nothing wrong," he said, alleging a link between his ban this week and the unspecified bribe offers.
Akhtar was banned for five years for repeated disciplinary breaches, effectively ending the maverick paceman's controversial career.
The 32-year-old appeared before a disciplinary committee charged with publicly criticising the country's cricket board. He was already on two years' probation for hitting a team-mate with a bat last year.
Akhtar, whose 11-year career has been plagued by injuries, discipline problems and a doping scandal in 2007, has vowed to appeal the ban with the Pakistan Cricket Board and take the matter to the civil courts if required.
"I don't want to sensationalise things, but by saying this I want to let the people know how much I love to play for my country and I have never tried to damage the name of my country," he said in the interviews.
"Even in India I was offered money to under-perform and on various other occasions but I told the people who offered me money to run away or I will let loose," said Akhtar.
"I never tried to sell cricket or my country's name. I was never tempted by money. I have played my cricket clean but the ban has hurt me badly."
Akhtar, who has taken 178 wickets in 46 Tests and 219 in 138 one-day matches, did not specify when he was offered the massive bribes.
But he was part of the Pakistan team that toured India twice in 1998 and 2007 and South Africa in 2002, 2003 and 2007.