US President Barack Obama made contact with Iranian officials and even gave his approval for Iran to begin a nuclear programme in 2011 during covert talks with Iranian officials, Iran's Supreme Leader Ayatollah Ali Khamenei revealed in a recent speech.

The comments made by Iran's Supreme Leader contradicted those of the Obama administration, which claimed that it only started talking to Iranian officials after the current president, Hassan Rouhani, was elected to his post in August 2013, Fox News wrote.

In his speech, Khamenei disclosed that talks between the US and Iran began during the term of the anti-Semitic, Holocaust-denying Iranian President Mahmoud Ahmadenejad, Rouhani's predecessor.

It was at this time that Obama allegedly endorsed Iran's right to have a nuclear programme.

"The issue of negotiating with the Americans is related to the term of the previous [Ahmadinejad] government, and to the dispatching of a mediator to Tehran to request talks," said Khamenei in his speech, as translated by the Middle East Media Research Institute.

"At the time, a respected regional figure came to me as a mediator and explicitly said that US President [Obama] had asked him to come to Tehran and present an American request for negotiations," Khamenei revealed.

"The Americans told this mediator: 'We want to solve the nuclear issue and lift sanctions within six months, while recognising Iran as a nuclear power.'"

"I told that mediator that I did not trust the Americans and their words, but after he insisted, I agreed to re-examine this topic, and negotiations began," Khamenei continued.

According to a senior Iranian official, Hossein Sheikh Al-Islam, US Secretary of State John Kerry sent a letter to Iran saying that the US "recognises Iran's rights regarding" nuclear enrichment, The Washington Free Beacon wrote.

"We came to the [secret] negotiations [with the United States] after Kerry wrote a letter and sent it to us via [mediator Omani Sultan Qaboos], stating that America officially recognises Iran's rights regarding the [nuclear fuel] enrichment cycle," Al-Islam said, according to the Middle East Media Research Institute.

"Then there were two meetings in Oman between the [Iranian and US] deputy foreign ministers, and after those, Sultan Qaboos was dispatched by Obama to Khamenei with Kerry's letter," Al-Islam said.