The PCB chief said since the ICC has chosen to stay away from issue, WADA had no business interfering in the 'internal matters' of Pakistan cricket.
''If WADA has any reservations, it should first approach the ICC, the global governing body of the game. The PCB has not received any written objection from any quarter regarding the lifting of bans on Shoaib and Asif not even from the ICC. So the doping chapter is closed now,'' Mr Ashraf was quoted by the local media as saying.
Mr Ashraf once again denied having any influence in the lifting of the bans on the two bowlers.
''I swear to God that we did not have any wrong intentions. The PCB carried out the tests in a transparent manner. PCB rules applied to whatever were the results (of the Tests). If this had happened in any other country that country's rules would have applied on it,'' he said, referring to the doping scandal which saw both Shoaib and Asif test positive for banned anabolic steroid nandrolone.
The duo was found guilty by the PCB anti-doping tribunal but was acquitted by an appeals committee. The acquittal sparked off criticism from the World Anti-Doping Agency, which is now contemplating legal action against the Pakistani board.
However, Dr Ashraf said the controversy was over.
''The matter is over. It's Pakistan's internal matter,'' he said.
But WADA is not willing to treat the issue as an internal matter of Pakistan and after chief Dick Pound lambasted the PCB for its ''aberrational'' handling, Director-General David Howman called for sanctions against the board.
''Should that go without a sanction? This doesn't fit with the whole process that we have in place globally. So that is of some concern on the face of it,'' Mr Howman told 'Cricinfo'.
''...it would be most unusual that athletes who have in essence accepted that they had the banned substance in their bodies they didn't challenge the analysis by even getting the B tests analysed,'' he added, raising doubts over the entire trial conducted by the PCB.
Mr Howman said WADA would decide its next move after meeting ICC officials this week