An independent inquiry has found no evidence that South Africa supplied weapons to Russia, President Cyril Ramaphosa has said.
The panel rejected claims made by the US ambassador to South Africa that a Russian ship was loaded with ammunition and arms in Cape Town last December.
The allegations had raised questions over the country's professed neutrality in the war with Ukraine.
Mr Ramaphosa said it had damaged the nation's currency and reputation.
"The panel found that there was no evidence to support the claim that the ship transported weapons from South Africa destined for Russia," the president said in a televised address to the nation on Sunday.
"No permit was issued for the export of arms and no arms were exported."
A spokesperson for the US embassy in Pretoria said the US appreciated the seriousness with which South Africa had investigated the claims but declined to comment on the report's contents.
The inquiry found instead that the Russian cargo ship had delivered a consignment of weapons from Russia to South Africa, ordered in 2018.
Ambassador Reuben Brigety's claims referred to the docking of Lady R in the Simon's Town naval base between 6 and 8 December 2022.
He told a media briefing in Pretoria in May he was "confident" weapons and ammunition were loaded to the vessel "as it made its way back to Russia".
A day later, South Africa's foreign ministry said Mr Brigety had "apologised unreservedly" for the claims.
Writing on social media after the meeting, Mr Brigety said he was "grateful for the opportunity to... correct any misimpressions left by my public remarks".
Mr Ramaphosa ordered an independent judge-led inquiry in the wake of Mr Brigety's comments.
"None of the persons who made these allegations could provide any evidence to support the claims that had been levelled against our country," Mr Ramaphosa said following the inquiry's conclusion.
The president will only be releasing an executive summary of the report, for security reasons.
The inquiry had visited the naval base, heard from almost 50 people and reviewed more than 100 documents, Mr Ramaphosa added.
South Africa has sought to maintain friendly relations with Russia since its invasion of Ukraine in February 2022, drawing criticism from the US and other Western nations.
It is one of only a handful of nations that has abstained from a number of UN votes on the conflict, refusing to publicly condemn Russia on the matter.
The US has previously raised concerns about joint naval exercises between Russia and South Africa.