"We are prepared to push the envelope and use our platform to promote freedom of expression and to encourage debate and conversation among our diverse subscriber base," said TopTV's air-time sales spokesman, Jean Meyer.

He said the aim was to give TopTV subscribers the opportunity to decide for themselves whether they wanted to see the fast-food franchise's ad.

The ad begins with people jumping a border fence to enter South Africa. A voice-over says: "You know what's wrong with SA? - it's all you foreigners."

The ad then shows people of different races across the country who disappear in a puff of smoke until only a Khoisan is left. He turns to the camera and says: "I'm not going anywhere. You @&*$# [swear word beeped] found us here."

Meyer said TopTV applauded Nando's for tackling "thorny" issues.

"The positive message contained in the advert, with the line, 'Real South Africans love diversity', is a sentiment that all South Africans should embrace."

The SABC, M-Net, DStv and e.tv all refused to air the ad.

SABC spokesman Kaizer Kganyago told the Cape Times that this was because the ad might incite attacks on foreigners. A print version of the ad was published in the Sunday Times. A banner at the bottom of the full page ad read: "Unlike our broadcasters, we're giving you the right to choose."