"This is the biggest crime that was committed in Croatia," Mesic said on state radio commenting on the Maestro operation, which saw six HFP officials, including three vice presidents, arrested on Saturday for taking about one million euros in bribes.
Mesic said the ministers on the HFP Steering Committee should be held accountable if any irregularity was established in their work.
"If it is established that anyone in any way took part or enabled another person to take part in those unlawful activities, the prime minister will have to take steps that will cost some people not only their positions in the supervisory board, but in the government as well."
Mesic said the state was damaged by hundreds of millions of kuna as hundreds of companies were bought without bid invitations.
"What happened was that bids would be invited, then everyone would be notified that the invitation was annulled and the company would be sold to someone else who offered more (to enter the deal)."
Mesic said that every privatisation carried out since the HFP's establishment should be examined, but he could not estimate how many would be declared void. "Many will be surprised when the names of the persons who took part in this big crime are revealed."
Mesic said the incumbent government should not be accused for everything because the facts in the HFP scandal should be established first. However, he defended the previous coalition government, saying the main culprits were brought into the HFP long before the coalition government came into power in 2000.
The president said the ministers in the HFP's supervisory boards should have known what was going on in the Fund and that they would have a lot to say in the investigation.
He asked the parliament and the government for an investigation of the voucher privatisation, saying that for some time he had been asking for investigating how individuals had bought war victims assistance funds and transformed them into holdings which now own dozens of hotels.
Justice Minister Ana Lovrin told state radio she did not about Maestro and that her ministry had no influence on the operation as such actions fell within the jurisdiction of the State Prosecutor's Office, the police and the Security and Intelligence Agency.
The six arrested were questioned by Zagreb County Court investigating judge Boris Ivancic at 10 am on Monday.
They are suspected of creating conditions on the stock exchange so as to be able to purchase shares and commit financial wrongdoing with the state's real estate put at the HFP's disposal.