Opposition parties have reacted with alarm and have called for action after allegations that arms-deal kingpin Schabir Shaik bribed former transport minister Mac Maharaj for a tender.

The Sunday Times reported that Shaik allegedly paid more than half a million rand to Maharaj during the period in which his companies were among those rewarded a R2,5-billion tender for the upgrading of the N3 highway.

The Democratic Alliance said it would ask the Public Protector and the Auditor-General to investigate dealings between Maharaj and Shaik, who is being investigated by the Scorpions for his role in the multibillion-rand arms deal.

DA transport spokesperson Stuart Farrow said on Sunday that the dealings between the men appeared to be "fraught with favouritism and bribery".

The DA would also ask President Thabo Mbeki to question the validity of contracts signed by the cabinet during Maharaj's tenure.

New National Party transport spokesperson Keppies Niemann called for a judicial commission of inquiry into all tendering processes.

He said an increasing number of instances of tender fraud were coming to light at all levels of government and that only a judicial commission would be able to make appropriate recommendations for stricter guidelines.

United Democratic Movement leader Bantu Holomisa supported the call for a judicial commission, but wanted it to include an audit of all companies awarded major tenders by the ANC-led government.

"This looting spree must come to an end," Holomisa said, adding that this was a continuation of the corruption that had occurred during the apartheid years.

The Inkatha Freedom Party and the Pan Africanist Congress both called for justice to take its course.

It is understood that the Scorpions' probe of Shaik has been extended to include Maharaj and a number of government officials, but Scorpions spokesperson Sipho Ngwema would not comment on this.

Maharaj said on Sunday he was unaware of an investigation, but vowed to co-operate.

"All contracts awarded by the Department of Transport during my term of office are a matter of public record," he said.

The newspaper said it was in possession of documents that show Shaik or his companies deposited amounts ranging from R10 000 to R75 000 into the accounts of Maharaj and his wife Zarina between 1998 and 2000.

According to the report, Maharaj and his wife received more than R500 000 from Shaik, most of it before Maharaj left the cabinet in 1999. It stated that Maharaj did not declare these "gifts", in the form of at least nine payments, to parliament's register of members' interests.

Shaik is the chief of Nkobi Holdings and a director of Nkobi Investments. The latter forms part of the N3 Toll Road Consortium, which was awarded a tender to upgrade the road from Johannesburg to Durban.

Citing personal reasons, Maharaj announced he would step down in November 1998, during the period when the alleged bribes were paid.

With acknowledgements to Christelle Terreblanche and The Star.