Suspended chief executive Dali Mpofu is threatening to take the SABC to court unless his suspension is reviewed.
Though Mpofu yesterday refused to comment, SABC spokesman Kaizer Kganyago confirmed that they had received the letter.
"The letter is confidential. I have not seen it. He sent it to the board's chairman Kanyi Mkonza and acting group chief executive Gab Mampone.
"It is not court papers. We are waiting to see whether he will take the matter to court," said Kganyago.
Mpofu was suspended by the board last Wednesday for, among others, "failing to implement decisions of the board".
Barely a day earlier, on Tuesday, Mpofu had suspended head of news and current affairs Snuki Zikalala for allegedly leaking sensitive information to ANC treasurer Matthews Phosa.
The ANC heavyweight has reportedly vehemently denied receiving any confidential document related to the corporation from Zikalala. At the weekend Communications Minister Ivy Matsepe-Casaburri said in a statement that Mpofu was suspended because the organisation lost its soccer and cricket broadcasting rights.
The Premier Soccer League's exclusive TV rights to all fixtures were awarded to SuperSport International last year for R1billion over five years. The deal was finally sealed despite Mpofu's claim that the SABC had the first option to the soccer rights.
This, according to sources, meant a loss of at least R2billion for the SABC.
This was a major blow for the SABC as it had already lost the rugby and cricket broadcasting rights to SuperSport.