Johannesburg - The SA Municipal Workers Union (Samwu) in the Eastern Cape on Tuesday said it was opposed to Numsa's expulsion from Cosatu.
"The defence of Cosatu includes in our view defending Numsa as we remain opposed to the dismissal of Numsa in Cosatu because they also seek to defend the soul of the federation," provincial secretary Siphiwo Ndunyana said in a statement.
"The reason why we defend Cosatu is that there is a grouping that is hell-bent on liquidating Cosatu to be a sweetheart union of the ruling class and the party.
Ndunyana said the unions which voted to expel the National Union of Metalworkers of SA (Numsa) did not understand how the Congress of SA Trade Unions operated, as every affiliate had the right to make their own resolutions.
"There is nothing sinister in what Numsa has done except just an agenda to defend the neo-liberal agenda and donate Cosatu on a [silver] platter to the highest bidders by those opposed to the progressive and radical trade union movement."
Numsa was expelled from Cosatu during a special central executive committee meeting which ran into the early hours of Saturday morning.
During the meeting Numsa presented its argument to Cosatu on why it should not be expelled, but this did not stop its ousting by 33 votes to 24.
Numsa has been at loggerheads with Cosatu since its general secretary Zwelinzima Vavi was suspended last year for having an affair with a junior employee.
She originally claimed he had raped her but did not press charges with the police. Numsa took Cosatu to court to reverse the suspension, where it won its bid and Vavi returned to work.
Numsa held a special national congress in December where it resolved not to support its traditional ally the ANC in the general elections.
Cosatu charged Numsa with contravening its constitution.
The SA Communist Party political bureau on Tuesday said it was regrettable that Cosatu was left with no option but to expel Numsa.
"For many months, throwing reckless insults in all directions, the Numsa leadership has shown no inclination to seek constructive and unifying solutions to the many challenges confronting the organised working class," SACP spokesman Alex Mashilo said in a statement.
"This was not a case of an externally manipulated witch-hunt, but a case of self-expulsion."
The SACP called on members of Numsa not to follow the union's leadership and to remain where they could help re-build unity in Cosatu.