Failure by Pretoria to hold those responsible accountable will result in severe consequences, the State Department has said

Washington has accused South Africa of harassing and intimidating US officials who it said were recently detained by Pretoria while carrying out duties linked to humanitarian support for the Afrikaner minority group. The dispute is the latest escalation in strained relations between the two countries.

The accusation follows a South African law enforcement operation on Tuesday at a facility processing applications from Afrikaners seeking refugee status in the US over claims of racial persecution.

Pretoria said it arrested and deported seven Kenyan nationals who were working without permits at the refugee center after entering the country on tourist visas. Reuters also reported, citing a source, that two US Citizenship and Immigration Services officers were briefly detained and later released during the operation.

In a statement on Thursday, the State Department condemned the detention of the officials and the alleged public release of their passport information as "an unacceptable form of harassment."

"This can only be seen as an attempt to intimidate US government personnel," it said, warning that failure to hold those responsible accountable could bring "severe consequences."

"The United States will not tolerate such behavior toward its government's officials - or toward any of its citizens - who are legally and peacefully operating abroad," the State Department said.

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South Africa's Home Affairs Ministry said no US officials were arrested. The Department of International Relations and Cooperation (DIRCO) also issued a statement on Thursday, calling Washington's claim "an unsubstantiated allegation."

It said Pretoria would not "negotiate its sovereignty and the implementation of the rule of law," adding that bilateral engagement with the US must be grounded in "mutual respect and factual dialogue."

The incident adds to diplomatic friction between the two countries since US President Donald Trump returned to office in January. His administration has taken a tougher line toward Pretoria, including imposing higher tariffs in opposition to South Africa's domestic and foreign policies and claiming Pretoria is enabling "genocide" against its white minority.

Washington has since launched a controversial refugee initiative that prioritizes asylum claims from white South Africans, particularly Afrikaners, who are descendants of Dutch settlers.