The State Capture Inquiry will hear expert evidence from Jan Gilliland from the National Treasury in Parktown, Johannesburg on Monday.
Chairperson of the commission Deputy Chief Justice Raymond Zondo is also expected to deliver his decision on applications for leave to cross-examine.
"The legal team is [also] in the process of identifying and/or consulting with other witnesses, who will be called to appear before the commission over the next few weeks," the commission said.
So far, five witnesses have testified.
Last week, acting government spokesperson Phumla Williams accused former communications minister Faith Muthambi of "torturing" her.
Williams implicated Muthambi at the inquiry on Monday, accusing her of wanting to "steal at all cost" from the Government Communication Information System (GCIS).
She told the commission the Muthambi appointed a junior to act as the director general, bypassing three deputy directors general, and ultimately rendered GCIS dysfunction during her time as minister.
Williams claimed that Muthambi had also stripped her of 70% of her functions as deputy director general, including her responsibilities over supply chain management and finances.
Muthambi released a scathing statement on Tuesday lashing out at Williams and labelling her a liar, following her testimony on Friday and Monday at the state capture inquiry.
"Phumla Williams is one of the most shameful manipulators and liars that I have ever had the displeasure to encounter," Muthambi said in the statement.
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