Former prime minister Tony Abbott says Home Affairs Minister Peter Dutton is "absolutely right" about the need to prioritise white South African farmers through Australia's refugee program.

Wading into the internal and diplomatic furore over Mr Dutton's remarks, Mr Abbott said the situation in South Africa was a "national crisis" and "racism of the worst sort", and backed the call for intervention - despite Foreign Minister Julie Bishop rejecting the idea at the weekend.

Former prime minister Tony Abbott and Home Affairs Minister Peter Dutton. Credit:Andrew Meares

"There is a very serious situation developing in South Africa. Something like 400 white farmers have been murdered, brutally murdered, over the last 12 months," Mr Abbott told 2GB radio.

The farmers were being murdered by "squatters intent on driving them off their land", he said, and it would be a "national crisis" if the same thing were happening to Australian farmers.