Political parties on Monday welcomed reports that Defence Minister Mosiuoa Lekota had suspended head of acquisitions Shamin (Chippy) Shaik from his post, but some questioned why it had taken so long.

Parliament's public accounts committee (Scopa) chair Dr Gavin Woods said Shaik should have been suspended from the beginning of the investigation into the multi-billion rand arms deal.

"I agree with the minister's actions... but one might ask why Mr Shaik wasn't suspended from the time the investigation began seeing that he was a critical figure in the investigation," he said.

Lekota said in Pretoria the suspension followed allegations that Shaik had disclosed classified information without authorisation in violation of the law.

"He is to be immediately removed from the premises and will not be allowed to enter any military installation or the headquarters of the department of defence."

He said the alleged transgression was committed between October 1 and November 1 this year.

The information allegedly improperly disclosed to members of the public by Shaik did not relate to the three-agency probe into South Africa's multi-billion rand arms deal, the report on which was released last week.

It was also unrelated to charges against Shaik's brother, Schabir, who appeared in court on Friday after classified documents, including cabinet minutes were allegedly found in his possession, Lekota said.

Democratic Alliance public accounts spokesperson Raenette Taljaard said it seemed strange that Shaik had been suspended on the basis of recent transgressions on which no detail had been made available by Lekota.

It was also strange given the finding of the joint investigating team that Shaik had no security clearance and would not legally have had access to the information he was accused of sharing with the public.

"In the absence of further detail from the minister of defence the impression is created that Mr Shaik is being removed from the public eye... until such time as the furore around the investigation dies down," she said.

Gerhard Koornhof of the United Democratic Movement said the suspension was "after the fact" and raised serious questions about what information Shaik shared with cabinet ministers.

"Mr Shaik had such a powerful position and he was dealing with such powerful politicians.

"The question now is... how did he get the information and did he share it with cabinet.. and what relation did he have with the ex-minister of defence (Joe Modise)."

It was good to "nail" an official but officials were only there to relay the orders of politicians, he said.

"This (the suspension) cannot stand on its own, it is all interrelated."

Koornhof said he would definitely pursue the matter at Scopa's meeting on the arms deal report on Wednesday.

Lekota said he had asked Public Service and Administration Minister Geraldine Fraser-Moleketi to conduct an independent investigation into the allegations.

Shaik was suspended with full pay pending the outcome of this investigation.

The probe into the arms deal - conducted by the auditor-general, national directorate of public prosecutions and public protector - found that there had been a conflict of interest in Shaik's role in the procurement of the strategic arms package.

This arose from the shareholding of his brother Schabir in the Thomson Group and African Defence Systems which benefited from the arms deal.