Malcolm Turnbull has defended Australia’s refugee policies, describing them as “non-discriminatory”, but pointedly refused to condemn or back comments by the home affairs minister, Peter Dutton, that white South African farmers could receive “special attention” from Australia.

Commenting on a documentary about violent rural crime in South Africa, Dutton said farmers deserved “special attention” and should receive fast-tracked humanitarian visas from a “civilised country”.

“I do think, on the information that I’ve seen, people do need help and they need help from a civilised country like ours.”

Dutton’s comments have sparked a formal complaint from the South African government with Pretoria hauling in Canberra’s high commissioner to demand a retraction.

Speaking at the Asean Australia summit in Sydney, the prime minister was asked specifically whether he backed the home affairs minister’s position. He neither defended the comments nor condemned them.

“Our program is thoroughly non-discriminatory,” he told reporters. “You have asked me about the situation in South Africa – we have a very large South African community, or Australians of South African ancestry, from every background, and they also make a phenomenal contribution to our very successful multicultural society.”

The Greens leader, Richard Di Natale, claimed Dutton was trying to bring back the White Australia policy.



“The bloke is an out and out racist,” Di Natale told reporters in Melbourne. “He’s pitching to One Nation voters in Queensland.”



Several Coalition colleagues have defended Dutton despite calls from South Africa for him to withdraw.



Pretoria flatly rejected his suggestion white farmers are facing “horrific circumstances”.



The assistant treasurer, Michael Sukkar, said suggestions Dutton was being racist were “laughable”. The government had already been able to help Syrians and Iraqis under its refugee program.



“Now, when other issues emerge, including these persecuted white farmers, I think it’s wholly appropriate that we look at it because there are persecuted groups all around the world,” he told Sky News on Friday.



The Australian foreign affairs minister, Julie Bishop, denied there was a double standard in Dutton speaking up for white South African farmers but not Palestinian farmers persecuted by Israel.



“I reject that,” Bishop told ABC radio. “What we do in our humanitarian visa program is assess visas on their merits and that’s what Peter Dutton as home affairs minister does every day.”

But the minister said she and Dutton were working to determine if any changes were needed to the offshore humanitarian visa program.



Bishop said Australia’s high commissioner, Adam McCarthy, was in regular contact with the South African government about Australian concerns.



She said Australia wanted the nation to ensure the safety of all citizens and ensure any changes to land ownership would not disrupt the economy or lead to violence.



The Labor leader, Bill Shorten, said he did not know what motivated Dutton to make the comments.



“There are some media reports that would indicate some farmers are experiencing difficulty,” Shorten told ABC radio. “I have to say though I also read media reports that other South Africans can be the victims of crime.”

• Australian Associated Press contributed to this report