However, there was so far no official instruction to open an investigation paper on the claim, said MACC management and professional division deputy commissioner Jamidan Abdullah.
The commission would issue a statement on the matter soon, he said after attending the signing of the MACC-promoted Corruption-Free Pledge (IBR) by the National Water Services Commission (SPAN) here today.
Last Tuesday, Mahathir said when he was the prime minister, Zahid made an assets declaration that he had RM230 million in his bank account after his appointment as Umno Youth chief.
However, Mahathir acknowledged he had no proof to substantiate his allegation.
“At that time, he (Zahid) gave a verbal account to me, and I did not take it seriously.
“He explained that the money came from his businesses and, although I had my doubts, I had no proof then.
“Now he should answer how he accumulated so much money,” said Mahathir.