The Congress of South African Trade Unions (Cosatu) general secretary Zwelinzima Vavi will not apologise for linking Communications Minister Siphiwe Nyanda to a complaint that reports of corruption are not investigated, his counsel said on Friday.

"He hasn't received that letter yet, even though it is in all the newspapers," said Cosatu spokesperson Patrick Craven of a letter demanding a public apology and a retraction.

"I am confident that he will not be apologising, because he has nothing to apologise for," said Craven.

Craven explained that Vavi recently delivered a speech in which he complained that newspapers continued to carry stories of allegations of corruption against ministers, but that the President and the Cabinet had yet to say that these allegations would be investigated.

No names were mentioned in the written speech.

When a reporter later asked Vavi which ministers he was referring to, he named Nyanda and Local Government Minister Sicelo Shiceka.

The Mail&Guardian had reported earlier that Nyanda ran up R500 000 in hotel bills in Cape Town waiting for his official residence to be ready, and that Shiceka allegedly doctored his curriculum vitae.

"He wasn't making any fresh allegations," said Craven. These are people against whom allegations have been made, and that is public knowledge."

Nyanda disagrees.

"We have proceeded to demand a retraction and an apology from Mr Vavi for allegations which are calculated to be understood by an audience that our client is morally reprehensible and that he is corrupt," said Siyabonga Mahlangu, director of litigation at Edward Nathan Sonnenbergs.

This, after reports that the ANC planned to subject Vavi to a disciplinary hearing for the comments.

Cosatu has described the move as unprecedented and has said it would destroy its alliance with the African National Congress (ANC) and the South African Communist Party (SACP).

Mahlangu said that the firm had not been briefed to deal with the details of the story, but Nyanda wanted the retraction of the defamatory allegations made against him, and an unqualified apology, by June 10.

"Our courts have ruled that a repetition of a defamatory statement in itself constitutes a cause of action against a person repeating such defamatory allegations."

The demand is that Vavi's retraction and apology must be published in the same matter and through the same media that he used when he made the statement.

Nyanda's lawyers were not instructed to demand an apology from the publications that carried the allegations.

The firm believed "in freedom of the press and the media's duty to inform the nation" and that courts applied different standards to the press. He said the legal team would "take a view" if Vavi did not comply.

"What the minister wants to protect, is to protect his right to his good name and to his dignity as a person," said Mahlangu.

"He moves from a premise that as a public representative he still maintains his rights to his dignity and his good name and that in fact, it is upon such dignity and such good name and reputation that he was entrusted with public responsibilities," he said.

The team was waiting to hear from Vavi whether he had explanation or facts that could be brought to Nyanda's attention that would inform how the team proceeded with the matter.