The Congress of SA Trade Unions has expelled its general secretary Zwelinzima Vavi.
Cosatu's central executive committee reportedly voted to expel Vavi by 30 votes to one.
On Sunday, Vavi said he was not resigning from the federation.
The federation is currently holding a high-level Central Executive Committee meeting and is expected to formally announce Vavi's expulsion at a press conference at noon on Tuesday.
In his reaction to the news, Numsa general secretary Irvin Jim said Cosatu's CEC had succeeded in doing something the apartheid government could not do - destroy a labour federation.
