It said in a statement Duda was suspended because it received “certain information” about her from two internal investigations.
The information was linked to procurement and financial irregularities.
“The board…has been able to pick up these alleged transgressions after amending its policies to comply with principles of good governance and proper financial management,” it said.
“The board wishes to express its profound concern and disappointment at these alleged irregularities, which have the potential to severely undermine both good governance and the financial stability of the corporation.”
It requested a full investigation of the irregularities, and would report its findings to Parliament once it was concluded.
“In line with principles of fairness and good labour practice, we appeal to the public to allow the board to complete these processes in accordance with the law,” the statement said.
“We believe that such a process will determine the innocence or not of those concerned.”