National Metalworkers Union of SA general secretary Irvin Jim has accused the Democratic Alliance of trying to undermine the ANC leadership.
He was speaking at a Workers Day rally in the Northern Cape.
Jim referred to the DA as a "Mickey Mouse" organisation, saying it continued to paint a picture that it was better than the ruling party.
He called on those gathered at the rally in Kuruman to be united and to keep the African National Congress in power.