Relations between the two countries have been on a downward spiral since President Donald Trump returned to office early last year, with the US leader cutting aid, expelling the South African ambassador and offering “refuge” to white South Africans fleeing “persecution.”

The South African government has repeatedly rejected allegations that it is persecuting white people or confiscating their land.

It said claims of a white genocide had been widely discredited and lacked reliable evidence.

South Africa’s latest crime statistics do not indicate that white people are at a greater risk of violent crime than other racial groups.

Trump offered refugee status to Afrikaners last year after South African President Cyril Ramaphosa signed a law allowing the government to seize land without compensation in rare instances.

The legislation allows the state to expropriate property in the public interest and provides for circumstances in which compensation may be set at zero. But it also requires authorities, in most cases, to first try to reach an agreement with property owners, and disputes can be taken to court.

Land ownership remains a highly sensitive issue in South Africa more than three decades after the end of apartheid, under which the black majority was dispossessed of land and denied many basic rights.

The government says land reform is necessary to address those historic inequalities and insists the new law does not permit arbitrary seizures.

Most private farmland is owned by white South Africans, who make up just over 7% of the population.

In Wednesday’s statement, South Africa’s government said: “It is our sovereign right to put in place laws that address the nation’s concern over centuries of racial injustice.”

In a separate social media post on Tuesday, Rubio accused South Africa’s government of pursuing “racial grievance against the Afrikaner minority” and said those responsible for what he described as injustices “have no place in the United States”.

He said the South African government had failed to adequately address US concerns about what Washington describes as “government-sponsored discrimination” against Afrikaners and other minorities.

“The United States will not allow such behaviour to go unchecked,” he added.

He said the actions targeted by the policy undermined “peace, economic stability and the rule of law.”

The US embassy in Pretoria said Washington believed dialogue with South Africa had run its course and accused the African country of failing to demonstrate a commitment to strong bilateral relations.

It warned that the new visa restrictions were the beginning of tougher measures, adding: “This visa restriction policy is only the first step in a series of escalatory measures that will show America’s firm resolve in this matter.”

South Africa made efforts to soothe tensions with US, with Ramaphosa going to the White House in May last year with a large delegation that included white members of his coalition government and also famous white South African golfers.

But Trump ambushed the Oval Office meeting with claims that white South African farmers were being killed and “persecuted” – producing unsubstantiated evidence that has been widely discredited.

Further efforts by South Africa to mend the relationship have failed, with Africa’s largest economy being hit in August with 30% tariffs on goods being exported to the US – the highest rate in sub-Saharan Africa.

The latest visa restrictions are being imposed under a provision of US immigration law that allows the secretary of state to bar foreign nationals whose entry is considered potentially damaging to US foreign policy interests.