The Department of International Relations and Cooperation (Dirco) is expected to reprimand US ambassador to SA Reuben Brigety for not following proper diplomatic channels to express his country's concerns that SA supplied arms to Russia.

"Dirco will today demarche the USA Ambassador to South Africa following his remarks yesterday. We'll issue a detailed statement after the meeting," Dirco spokesperson Clayson Monyela said on Friday.

He noted that International Relations and Cooperation Minister Naledi Pandor would speak to her US counterpart, Secretary of State Antony Blinken, also on Friday, to express SA's displeasure.

This comes after Brigety engaged South African media on Thursday and expressed his country's concerns that SA provided weapons and ammunition to Russia.

Brigety said America was convinced that SA, despite the fact that it claimed it took a non-aligned stance on Russia's invasion of Ukraine, had supplied arms to Vladimir Putin's army.

"Among the things we noted was the docking of the cargo ship in the Simon's Town naval base between 6th to 8th December, 2022, which we are confident uploaded weapons and ammunition onto that vessel in Simon's Town as it made its way back to Russia," the ambassador said.

Monyela noted that the National Conventional Arms Control Committee had no record of an approved arms sale by the state to Russia related to the period/incident in question.

"We, therefore, welcome the inquiry established by HE President Cyril Ramaphosa to establish the facts and role players. If any crimes were committed, the law will take its course," he said.

The Presidency said on Thursday that an independent inquiry would be held into the allegations.

On Friday, Minister in the Presidency Khumbudzo Ntshavheni distanced the SA government from the allegations.

"There was no official authorisation of weapons that were sold to Russia and Ukraine."

Those overseeing the vessel's arrival on local shores could detail what "cargo it took and brought in", Ntshavheni told talk radio 702.

Ntshavheni said the inquiry was specifically meant to reveal why the vessel arrived in South Africa and that it was not an admission of guilt.

"We have been provided information that it was here. But given we are going to undertake an inquiry, we cannot come to you now and say this is whatever. Because I don't want to go and testify on issues that have got nothing to do with me."