South Africa's bid to have two brothers from the wealthy Gupta family extradited from the United Arab Emirates (UAE) has failed.

Atul and Rajesh Gupta are accused in South Africa of profiting from their close links with former President Jacob Zuma and exerting unfair influence.

The justice ministry said it had learnt with "shock and dismay" about the move.

The brothers, who deny any wrongdoing, fled after a judicial commission began probing a major corruption scandal.

The Indian-born Guptas were arrested in the UAE last June and extradition talks with South Africa began.

But the UAE said that it turned down the extradition request on a technicality.

In a brief statement, quoted in the Emirates News Agency, it said that a review "found that the request did not meet the strict standards for legal documentation as outlined in the extradition agreement between the UAE and South Africa" that came into force two years ago.

Some of the paperwork was either incorrect, in the case of the fraud charge, or missing, in the case of the corruption charge, the statement adds.

The decision was made in February but it was only communicated to South Africa on Thursday, South African Justice Minister Ronald Lamola said.

"The reasons provided for denying our request are inexplicable and fly in the face of the assurances given by Emirati authorities that our requests meet their requirements," Mr Lamola is quoted by South Africa's Mail & Guardian newspaper as saying.

The UAE government says the "South African authorities are able to resubmit the extradition request with new and additional documentation".

Earlier, Mr Lamola had said his government would appeal against the decision.

In recent weeks there have been media reports that the brothers were no longer in custody and had been spotted in Switzerland.

The justice ministry could not confirm this or whether the brothers, who had been granted South African citizenship, had acquired passports from the Pacific island nation of Vanuatu.

The news is a blow for South Africa's fight to bring the Guptas to justice.

An official inquiry, known as the Zondo commission, took four years to probe allegations of high-level corruption under the Zuma presidency, exposing how billions of dollars were looted from state coffers.

It found that the brothers, who once enjoyed unfettered access to power that became known as "state capture", tried to influence political and economic decisions.

Many of the most serious allegations focus on their relationship with Mr Zuma, who was president of South Africa from 2009 until he was forced to step down amid a storm of corruption allegations nine years later.

The Gupta family is accused of using their close links with Mr Zuma to win business contracts, influence high-profile government appointments and misappropriate state funds.

Mr Zuma, along with the Guptas, denies the allegations.

South Africa negotiated an extradition treaty with the UAE in 2021, three years after the brothers fled the country.