South Africa has initiated urgent steps to halt the auction of the key to the jail cell on Robben Island where Nelson Mandela spent 18 of his 27 years as a political prisoner before becoming the country's first democratically-elected president.
The online auction on January 28 announced by US-based Guernsey's Auctions is expected to fetch more than a million pounds.
Sports arts and culture minister Nathi Mthethwa has ordered an investigation into reports that the key had been provided to Guernsey by Christo Brand, who was Mandela's jailer and later became a tour guide on Robben Island as part of reconciliation attempts after the anti-apartheid icon ascended to power.
Mthethwa said it was a serious matter, which is receiving attention at the highest levels.
He said the master key to the Robben Island cells was still there, so the investigation would determine whether Mandela's cell key was duplicated.
It is unfathomable for Guernsey's which is clearly aware of the painful history of our country and the symbolism of the key to consider auctioning the key without any consultation with the South African government the heritage authorities in South Africa and Robben Island Museum.
This key belongs to the people of South Africa...It is not anyone's personal belonging Mthethwa told the news channel EWN.
No individual has the right to possess this important object of cultural and heritage significance. Robben Island is a national monument and national museum, and is also a World Heritage Site, declared by UNESCO in 1999, and therefore is governed by so many heritage declarations, he said.
Anything that has to do with Robben Island is under the care of Robben Island Museum Council. Anybody who wants anything has to go through that, the minister said.
Mthethwa said his department had held a number of meetings on Friday, where it emerged that it might not only be the key that was being auctioned.
It is not only the key that has been taken out fraudulently unless proven otherwise, and we are following that up, the minister said.
The auction house earlier said that the items on auction included Mandela's eyeglasses a bronze cast of his fist, ceremonial pens he received from former US President George W Bush and the United Nations.
Mthethwa said there has been discussion with the auction house, Guernsey, which seemed to understand the history behind the key.
It is ironic that they seem to understand the painful past and the history of Robben Island, but nevertheless, they decided to proceed (with the auction) without consulting the government of South Africa or any other heritage authorities and we find that very bizarre...We will fight to ensure that we bring it back and if there are other objects, which is part of our investigation, we will do the same, Mthethwa said.
In a separate statement, the Ex-Political Prisoners Association has called for the arrest of the person responsible for selling the key.
In 2014, Brand released his book 'Doing Life with Mandela My Prisoner, My Friend' with co-author Barbara Jones, describing how he had assisted Mandela and others during his time as a prison warden on Robben Island and how he later became a dear friend to Mandela.
Mandela, who died aged 95 in December 2013, was elected as first president of democratic South Africa in May 1994 and served in the role until June 1999.