The Israeli president has slammed The Guardian newspaper for its claim that Israel offered to sell South Africa nuclear weapons in the 1970s.

Shimon Peres said the allegations had no basis in reality and demanded a correction after the newspaper accused Israel of holding secret negotiations with South Africa's defence minister, PW Botha, in March 1975.

The newspaper said an American academic had uncovered secret documents showing that as Israel’s defence minister, Mr Peres had offered three sizes of warheads to the apartheid regime.

Documents published alongside the report reveal the South Africans requested nuclear-capable warheads and that Mr Peres listed the weapons which were available for sale.

However the documents do not confirm a sale was proposed or that any nuclear material was transferred.

The report was based on research by Sasha Polakow-Suransky, whose book on the ties between Israel and South Africa will be published this week.

If the memos are accurate it would be the first documentary evidence that Israel has a nuclear arsenal, which has never been confirmed.

Mr Peres said no such documents existed and expressed regret Israeli officials had not been asked to comment.

He said: “Unfortunately, The Guardian elected to write its piece based on the selective interpretation of South African documents and not on concrete facts.

“Israel has never negotiated the exchange of nuclear weapons with South Africa. There exists no Israeli document or Israeli signature on a document that such negotiations took place.

Mr Peres is planning to write a harsh letter of complaint to Alan Rusbridger, The Guardian's editor.

An Israeli Embassy spokesperson said they were surprised The Guardian had devoted so much space to the subject.

They said: "As the Ayatollah’s regime stands no more than two steps away from acquiring nuclear weapons, we see it as a strange decision to dedicate the first three pages of a British newspaper to speculation based on a note that may or may not have been written 35 years ago.

"Such attempts to distract from the true threat of Iranian nuclear capability, would be met with great approval in a Tehran state newspaper.

The spokesperson added: "To add insult to injury the paper has also chosen to grace us with another dispatch from Chris McGreal on his favourite topic; Israel and apartheid.

"We reject Mr McGreal’s continuous smearing of Israel, which in the words of the President’s Office, “do an injustice to the readers, to history and to the truth.”