The Congress of South African Trade Unions (Cosatu) remains fully behind Deputy President Cyril Ramaphosa in his quest to become the African National Congress' (ANC's) next president, the trade union federation said on Monday.

It dismissed Ramaphosa’s alleged extra marital affairs as “silly” and as “a matter between him and his family”.

In a statement, spokesperson Sizwe Pamla said its decision to endorse Ramaphosa was never based on Ramaphosa's strict moral attitude.

“As Cosatu, we never said that we support him because of his puritanical qualities,” Pamla said.

"We are supporting him guided by the fight against corruption, ANC unity and defending and preserving the anti- Imperialistic character of the ANC."

In its report, the Sunday Independent linked Ramaphosa to at least eight extra marital affairs.

The article was based on private email correspondence in their possession. The newspaper did not, however, name the women.

It said more reports would follow in coming weeks.

Ramaphosa has denied the claims, but admitted to one affair which he said ended eight years ago.

Pamla said while they agreed that the conduct and behaviour of those who hold public positions should be exemplary, the federation refused to act as the moral police, peeking into people’s bedrooms.

He said the allegations were a “non-scandal”.

“The silly attempts to use this non-issue to send the Deputy President to political exile will fail and the whole thing reeks of the worst elements of political correctness. We will not dismiss an entire person as rotten on the grounds of one component we don't like or disagree with,” Pamla said.

Cosatu has backed Ramaphosa’s assertions that the reports are part of a "smear campaign" using state resources.

The federation said similar tactics were used in the run up to the 2007 ANC elective conference that saw Zuma defeat then-president Thabo Mbeki.

“Unfortunately, in our assessment of the current political situation, we are witnessing the re-emergence of those past undemocratic practices, which were previously used in the run-up to the ANC 52nd Polokwane Conference, in particular the use of state institutions in factional battles,” Pamla said.

Cosatu, which has no voting powers at the ANC’s December elective conference, was instrumental in Zuma’s victory in 2007. It has since called for him to step down and has banned him from its activities.

In 2014 the trade union federation charged its then general secretary Zwelinzima Vavi, with nine charges including having a relationship with an employee. It later expelled him from the federation.