The African National Congress was accused on Wednesday of reintroducing racial categorisation, thereby polarising South African society.
The National Democratic Convention (Nadeco) criticised the ruling party for not regarding coloured people as African.
"This ... is nothing less than racialism and a callous disregard of the massive exploitation and oppression that the brown community in South Africa suffered in the apartheid past," the party said in a statement.
"The mere fact that the ANC tries to categorise those disadvantaged as a result of the past in different groups causes a new form of apartheid in South Africa."
It was a case of "being too black in the past and now being too white", Nadeco said.
The coloured community is distinctly African, it added, and underscored the commitment of the Constitution to non-racialism.
"The next logical step for the ANC will be that they will want to categorise which part of the black community was more disadvantaged than others, creating a massive racial meltdown."
The ANC, Nadeco said, should stop categorising and classifying South African citizens.
It was reacting to a reported statement by ANC spokesperson Smuts Ngonyama that the ANC's strategic objective was to fight for the liberation of black people in general, and the "African" in particular.
"Africans", he said, were treated as third-class citizens in the past while other non-white groups were treated as second-class.
Anti-apartheid activist Allan Boesak at the weekend said the ANC had reintroduced the "language of racial categorisation". -- Sapa