Although Iran and the United States cut formal diplomatic ties in 1980, Iran's Foreign Ministry confirmed on Tuesday that President Hassan Rouhani has recently exchanged letters with President Barack Obama.
Iranian Foreign Ministry spokeswoman Marzieh Afkham said the US president sent Rouhani a message of congratulations when he was elected, according to Reuters.
When asked by reporters about the tone of the letter, the New York Times reported, Afkham replied: “Unfortunately, the US administration is still adopting the language of threat... We have announced that this needs to change into the language of respect.”
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Obama first spoke of the direct communication between the rival leaders during an interview with ABC News broadcast Sunday.
Both presidents are due to address the United Nations General Assembly next week in New York, though according to Reuters they have no plans to meet.
Rouhani, a moderate elected in June, has said he wants to end his country's standoff with the US and its Western allies over Tehran's nuclear weapons program. He has also indicated he will increase personal freedoms for his people.
Progress remains limited however. On Tuesday, Iran's government restored its block on access to Facebook and Twitter, just one day after relaxing the ban on social media.
Meanwhile, Iranian supreme leader Ayatollah Ali Khamenei seemed to back Rouhani on Tuesday with a call for “heroic leniency” in Iran's disputes with the West.
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