The reasons given for the suspension of defence acquisitions chief Shamin (Chippy) Shaik were carefully calculated, a security expert and a private defence contractor said on Tuesday.

They differed, however, on the prime motive behind the explanation Defence Minister Mosiuoa Lekota gave when he announced Shaik's suspension on Monday.

Lekota said Shaik was removed pending an internal government investigation into allegations that he had disclosed confidential information without authorisation.

This had nothing to do with the three-agency probe into South Africa's multibillion rand arms deal, the minister said.

Institute for Security Studies director Jakkie Cilliers said the government clearly had to be seen to be acting after the probe concluded that Shaik had a conflict of interest in the arms procurement process.

Suspending Shaik on an unrelated charge appeared to have been the only way at this stage to achieve this.

"The government appears to be limiting itself to what it thinks can be proven."

Defence contractor Richard Young, who lost out when a company owned by Shaik's brother Schabir was awarded an arms contract, described the reasons given for the suspension as "manipulation".

Separating this action from the arms probe was very deliberate, he said.

"To link an official's suspension to the arms probe would amount to an acknowledgement of wrongdoing on the part of the government."

Lekota on Monday said the information Chippy Shaik allegedly disclosed also had nothing to do with charges against Schabir Shaik, who appeared in court on Friday after classified documents were allegedly found in his possession.

Investigators into the arms deal -- in a report released last week --found Chippy Shaik's conflict of interest arose from the shareholding of Schabir Shaik in the Thomson Group and African Defence Systems.

The companies were awarded a contract to provide combat technology for four corvettes to be acquired under the arms deal.

Young said the Department of Defence was clearly seeking to put distance between itself and Chippy Shaik.

"It was extremely manipulative to suspend Shaik on a charge not related to the arms probe while there were serious other findings against him."

Schabir Shaik described the move against his brother as a "strange development".

"To suspend a man from his post without really saying why is unacceptable," he told Sapa from Durban.

Schabir Shaik expressed confidence that he and his brother would be vindicated in the weeks to come.

With acknowledgements to Sapa and Hannes de Wet.