Johannesburg - Lawyers acting for Patricia de Lille, the Pan Africanist Congress member of parliament, have written to President Thabo Mbeki requesting all the information he used to decide to exclude the Heath special investigative unit from the probe into the government's R43 billion arms deal.

One of them, Cecil Burgess, said the information would be used to assess whether Mbeki had applied his mind to his decision. If they found he had not done so they would seek a judicial review of his decision.

De Lille, whose original allegations sparked off the arms investigation, was interviewed by Frank Kahn and Jan Lubbe, both advocates on behalf of the president, to assess her information. Based on their investigation, Mbeki told the nation in a live television address last Friday night that they had found no prima facie evidence of criminal activity.

But late that night De Lille received a telephone call from an undisclosed source, who said that the president had not reflected the view of the advocates' report, which insisted on a full investigation including Heath's unit, The Sunday Independent said.

This week, Penuell Maduna, the justice minister, released the Kahn-Lubbe report, which confirmed De Lille's information. It said that the Heath unit's involvement was "warranted and justified".

The report agreed with the public accounts committee that the investigation would best be conducted by a multidisciplinary team consisting of the investigative directorate: serious economic offences, the auditor-general, the public protector and Heath's special investigating unit.

"Due to the scope of the investigation, it is in our opinion imperative that all the agencies referred to above be involved at the earliest possible stage," the report said.

The report considered the problem posed by the constitutional court's decision on Heath. The court said someone other than a judge had to become head of the special investigating unit within a year.

On Friday, Lubbe issued a statement saying that after Maduna received the report, he had called to ask if there was prima facie evidence of a criminal offence, The Sunday Independent said.

Lubbe said prima facie evidence of a criminal offence was a legal term that referred to "sufficient evidence on oath to enable a court to convict a person". Such an assessment was normally made at the end of an investigation, not at the beginning.

This statement by Lubbe and other documents will be used by De Lille's lawyers to establish whether Mbeki had applied his mind to the decision to omit the Heath unit.

These developments came at the end of a week of rising political tension inside and outside the ruling African National Congress, tensions that have the potential to damage the reputations of prominent South Africans.

The parliamentary public accounts committee, at the centre of the row over the arms probe, had to abort its planned workshop early in the week after extensive meetings by ANC members of the committee behind closed doors.

On Monday, the committee is to debate whether to call Jacob Zuma, the deputy president, to explain his angry attack in a letter on Gavin Woods, the chairperson of the committee, and on the committee's report, which was adopted by the national assembly in November.

On Saturday, Lakela Kaunda, Zuma's spokesperson, said Zuma stood by "every word" in the letter, The Sunday Independent said.

"All he wants is a reply from the committee. He doesn't understand why they are demanding an inquiry based on a fishing expedition that assumes that governments are always corrupt," Kaunda said.

"He wants his response from parliament, and he sees no reason why he should be called to the committee, because what he had to say was in his letter. He made his position clear there."

But Woods said Zuma had criticised work that had been adopted by parliament.

"He didn't just question the quality of the work, he suggested very serious motives were attached to it. He accuses us of damaging relations with important countries," Woods told The Sunday Independent.

"You can't get much more serious criticism than that. I think the thinking and logic of the letter was confused. It's difficult to respond until we understand what the deputy president was trying to say."

With acknowledgement to News24.