The U.S. said it had placed Ajay, Atul and Rajesh Gupta and close associate Salim Essa on its sanctions list, describing them as "members of a significant corruption network." It said the Guptas used bribery and other acts to influence government contracts and misappropriate state assets.
Outrage in South Africa over the Guptas' close relationship with Zuma led the ruling African National Congress party to pressure Zuma to resign in 2018. His successor, President Cyril Ramaphosa, has vowed to crack down on the widespread graft that has eroded support for the ANC, which has ruled the country since the end of the harsh system of white minority rule known as apartheid in 1994.
The scandal also severely hurt investor confidence in South Africa's economy, the most developed in sub-Saharan Africa.
The Guptas are now the subject of a nationally televised commission of inquiry in South Africa that is probing allegations of corruption in government and state-owned companies. The three brothers live in Dubai and have refused to return and face the inquiry.
This week Zuma's son Duduzane appeared before the commission of inquiry and denied he and the Guptas were involved in any acts of corruption. Jacob Zuma, who was president from 2009 until 2018, has denied allegations of corruption. Separately this year he has been in court fighting allegations of receiving bribes related to a 1999 arms deal.
A report by the country's corruption watchdog has described how the Gupta brothers allegedly captured large parts of the country's levers of power, extending to influencing the appointment of Zuma's cabinet ministers.
The new sanctions forbid U.S. entities from conducting business with the Guptas and their related businesses or handling their assets.
The Guptas' business empire in South Africa, which included interests in technology, mining and media, started collapsing after major South African banks closed their accounts.
The corruption allegations were revealed during years of dogged reporting by South African media and activists. The U.S. statement praises "the critical role played by South Africa's civil society activists, whistleblowers and investigative journalists to shine the spotlight on the Gupta network's elicitation of criminal abuse of public office and other acts of corruption, which have deterred investment and impeded South Africa's economic growth."
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