South Africa's sports minister has waded into an escalating racism row after former Springbok rugby player Ashwin Willemse walked off air in the middle of a Saturday evening broadcast.

Sports and Recreation Minister Toko Xasa called for Mr Willemse's co-hosts Nick Mallett and Naas Botha to be suspended from the South African television channel Supersports after the winger hit out at them live on air.

Mr Willemse said he could no longer bear to be "undermined", saying he had been referred to as a "quota" Springbok, referring to a defunct system that ensured a certain number of black players were chosen for national teams.

He then added he "refused to be patronised by two individuals who played in an apartheid era".

It is unclear exactly what caused the outburst, but it stoked an outpouring of support for Mr Willemse, who was named South Africa's Player of the Year in 2003.

On Sunday, Ms Xasa added her own thoughts to the issue.

“The continued appearance of Mallett and Botha will be seen as an endorsement of their alleged racist behaviour‚” she said, according to TimesLive.

“This behaviour of entitlement by some white South Africans who continue to think that their whiteness represent better must come to an end. If it was not for a barbaric nonsensical apartheid system that privileged them, we could not have implemented [a] quota system to normalise an otherwise abnormal system.”

Broadcasters SuperSport said "they were aware of the on-air incident and are looking into the matter".