South Africa's rugby chiefs refused to resign yesterday despite threats that their failure to step down will see an end to international tours and the withdrawal of the famous Springbok emblem.

The South African Rugby Football Union (SARFU) executive will not quit as ordered at the weekend by the National Sports Council (NSC), the body with ultimate responsibility for sport in the republic, SARFU vice president Silas Nkanunu told the media after a four-hour crisis meeting in Johannesburg. The NSC ordered the controversial white-dominated SARFU executive to quit by April 11th or risk international isolation and the loss of the sport's 92-year-old Springbok emblem.

Nkanunu said the SARFU would seek an urgent meeting with the NSC to "discuss the impact" of its decision "on rugby, in particular, and sport, in general, not only in South Africa, but also in the rest of the world."

The executive saw no need to heed the NSC ultimatum, he added.

He made no mention of the union apologising for forcing President Nelson Mandela into court to defend his appointment of a judicial commission of inquiry into allegations of corruption and mismanagement in rugby.

Mandela's court appearance caused an outcry in South African rugby circles and led to the NSC's demand that the rugby union and its controversial boss, Louis Luyt, resign.

The NSC said yesterday that it was prepared to meet with SARFU.

It was also the last straw for major sponsor cellular phone company Vodacom, which pours 30 million rand (£4.3 milion) into the game annually.

Vodacom announced yesterday that it would not support the game if Luyt did not resign.

Pay television channel, M-Net, urged Luyt to resign, but denied reports that it would "block out" coverage of rugby if there were no changes to the sport's governing body.

M-Net holds the broadcast rights for the Super 12 and tri-nations series.

Its forthright boss Russell Macmillan said on a South African sports television programme yesterday that if the NSC managed to mobilise a boycott of international rugby, there would be no rugby to televise and SARFU's income would be "wiped out."

If the government decided to isolate rugby, the governments of New Zealand and Australia would probably follow suit, he said.

"We have to accept the reality that there is a real possibility of an international boycott of South African rugby."

Sports minister Steve Tshwete said yesterday that he would support the international isolation of South African rugby if the SARFU executive did not step down.

"There is no way rugby is going to be left the way it is now," he told television news.

Tswhete, the council and the game's major sponsors believe the SARFU is a major obstacle to change in rugby, a major sport which has been slow to change structurally since the apartheid era.

The NSC, a federation of the country's 143 sporting codes, said last Saturday it had decided to take drastic measures against the SARFU, not to kill rugby, but because it faced a crisis.

Rugby was given special dispensation by the NSC to carry on using the Springbok emblem after the intervention three years ago by Mandela ahead of the 1995 Rugby World Cup, which South Africa won.