The office of Iran's supreme leader, Ayatollah Ali Khamenei, published photos and video showing Khamenei at a ceremony on Saturday marking Arba'een, a day commemorating the death of Muhammad's grandson, Al-Husayn ibn Ali, after The New York Times reported a day before that he had fallen "gravely ill" with his situation considered to be critical last week.
The Times reported that he had since improved and was resting after undergoing surgery.
He was suffering from extreme stomach pains and high fever and is under the supervision of doctors, NYT said, citing four people close to the 83-year-old dictator.
The report claimed that Khamenei's office had canceled all of his meetings scheduled for last week as his health deteriorated.
Khamenei ill as Iran nuclear talks falter
The report of the Iranian leader's worsening situation came as the Islamic Republic's hopes to finalize the revival of the 2015 Joint Comprehensive Plan of Action (JCPOA) were all but dashed by the United States and Western powers due to the distance between the two parties during negotiations.
Last week, France, Germany and the UK criticized Iran's conduct in the talks, saying Iran "continues to escalate its nuclear program way beyond any plausible civilian justification."
Iranian Foreign Ministry spokesman Nasser Kanani said that the statement was "not constructive," accusing Europe of "taking a step in the direction of Israel, which wants the nuclear talks to fail."