The tripartite alliance secretariat met on Thursday amid uncertainty over reports that the African National Congress (ANC) Congress of South African Trade Unions (Cosatu) general secretary Zwelinzima Vavi.

ANC spokesperson Jackson Mthembu said that the secretariat meeting was a routine one.

It was about preparing for an alliance summit next month - between the ANC, the Cosatu, the South African Communist Party (SACP) and the SA National Civics Organisation (Sanco).

The ANC's national working committee on Monday reportedly discussed bringing charges against Vavi for accusing President Jacob Zuma of failing to act against corrupt ministers.

The reports elicited indignation from Cosatu and its affiliates. The SACP also entered the fray, saying such a move would be "reckless".

Mthembu would not be drawn on the matter on Thursday.

"We have always said that the ANC in its very nature only pronounces on decisions [taken]," he said.

"Somebody ill-disciplined spoke to you when there is something not properly processed... I am not confirming or denying anything."

The Times reported that Vavi wrote a letter to Mantashe on Wednesday, demanding an urgent meeting on questions about the news reports.

Vavi asked why decisions of the ANC national executive committee and the 19-strong national working committee were "communicated to the public by 'sources' who attend the meetings", the newspaper said.

It said that Vavi wanted to know how the ANC would dismiss Cosatu's charge that there was a grouping in the ruling party "hell-bent on destroying unity and cohesion of the ANC and that of the alliance".

Vavi also sought clarity on whether the ANC had changed its views on the need for the alliance and its historic promotion of dual membership. Cosatu spokesman Patrick Craven confirmed the letter was sent to Mantashe, but declined to elaborate on its contents.

He said Vavi had not been formally notified of any charges, and the ANC had not yet responded to Cosatu's request for a meeting to clarify the reports.

Mthembu did not rule out the possibility of further bilateral meetings between the alliance partners ahead of the important summit next month.

"It is likely that we could have some bilateral... we don't rule that out," he said.