Johannesburg - ANC secretary general Gwede Mantashe has compared Cosatu's largest affiliate the National Union of Metalworkers of SA (Numsa) to a person suffering from a lifestyle related disease, the Sowetan newspaper reported on Wednesday.

"Sometimes you have a chronic disease that is lifestyle related, [and] instead of behaving properly and doing the right thing, you blame witches," Mantashe was quoted as saying.

On Monday Numsa said it would forge ahead with the launch of its own political party, the United Front.

READ: Numsa breaks away from ANC alliance

The union, which has been at loggerheads with the Congress of SA Trade Unions, has withdrawn its support for the African National Congress, saying it no longer represents workers' interests.

Mantashe said the ANC could not impose its views on Cosatu, which bears the onus of working for unity.

This was after Numsa rejected as a "farce" an ANC task team's efforts at mediating Cosatu's internal tensions.

Cosatu said on Friday discussions about Numsa's future in the trade union federation would continue when the special central executive committee meeting, which adjourned last week, reconvenes on November 7.

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