The Congress of South African Trade Unions (Cosatu) is turning up the heat on its ally, the African National Congress (ANC), calling for the report on the controversial arms deal that the ruling party is compiling to be made public.

Cosatu spokesman Patrick Craven said yesterday the union federation did not approve of the document being for internal party consumption only.

The ANC and some of its leaders are in the limelight for alleged impropriety relating to the multibillion-rand arms deal. Opposition parties have called on President Thabo Mbeki to explain his role in the process, as he was deputy president and chairman of the relevant cabinet sub-committee when the deal was made. He is the latest ANC figure to be linked to alleged wrongdoing in the matter in which ANC president Jacob Zuma faces 16 corruption charges.

The ANC has appointed a committee consisting of ANC deputy president Kgalema Motlanthe, businessman Cyril Ramaphosa, treasurer-general Mathews Phosa, national executive committee (NEC) members Jeremy Cronin, Sankie Mthembi-Mahanyele, Siphiwe Nyanda and cabinet ministers Naledi Pandor and Lindiwe Sisulu to compile a "factual" report so the party can decide how best to support Zuma in his coming corruption trial.

ANC secretary-general Gwede Mantashe has said the purpose of the report is to inform the new ANC leadership about the arms deal. He repeated after the NEC meeting on Monday that the report would not be made public. It would be made available to the next NEC meeting, in May.

Craven said that the great public interest around the arms deal controversy had to be considered.

"Cosatu is ... concerned that the report will only be for the internal consumption of members of the NEC . Given the legitimate public interest and concern about this issue, it should be dealt with as openly and transparently as possible ," said Craven.

It is possible that Cosatu ­ which is meeting the ANC at the end of the month ­ may raise its call for the report to be made public.

However, the ANC is unlikely to accede to Cosatu's demands as it is on record that the document is for internal use. It may be shared with the tripartite alliance partners.

A probe by three government agencies ­ the Public Protector, the National Prosecuting Authority and the auditor- general ­ did not find the government guilty of wrongdoing in awarding the arms deal's primary contracts.

Despite investigations by German and British authorities, the government has resisted any suggestion that fresh allegations of irregularities in the arms deal require a new probe.

With acknowledgements to Amy Musgrave and Business Day.