Transnet chief executive Siyabonga Gama is due to know his fate on Monday.
The Transnet board has asked him and procurement officer Thamsanqa Jiyane as well as supply chain manager Lindiwe Mdletshe to give reasons why they should not be suspended.
This relates to violation of the Public Finance Management Act in awarding a major tender to supply locomotives.
The value of the tender escalated to more than R54-billion.
The Guptas are alleged to have received more than five-billion-rand in kick-backs from the transaction.
Jiyane and Mdletshe were suspended on Thursday last week.
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