Iran's supreme leader Ayatollah Ali Khamenei successfully underwent prostate surgery it was announced Monday, in an unprecedented public statement about his health, which has long been the subject of speculation.
The 75-year-old cleric, who has ruled since the death in 1989 of the Islamic republic's founder Ayatollah Ruhollah Khomeini, had a routine operation, according to IRNA, Iran's official news agency.
"There is nothing to worry about," the supreme leader said in a brief interview recorded before he entered hospital and then aired on state television.
"This does not mean that prayers are not welcome... but it is a normal operation," he added.
As the country's supreme guide, Khamenei has the final word on all matters of state and as such he outranks all politicians, including the country's President Hassan Rouhani.
As an example of his influence, Khamenei made a speech on July 7 that outlined Iran's demands under any nuclear deal with the West, two weeks before a deadline for an agreement was ultimately missed.
The doctor in charge of the medical team that conducted Khamenei's surgery said patients undergoing such a procedure tend to stay in hospital for between three and five days afterwards.
"This is true for him," Dr Alireza Marandi, a former health minister, told state television. "His health is totally good," Marandi said, but the effects of surgery will affect the leader's work rate for several weeks.
- President at bedside -
Rouhani, who was in the northeastern city of Mashhad on Sunday, was due to fly on to Kazakhstan but instead returned to Tehran to be at the hospital, a political aide said.
Official pictures showed the pair at the leader's bedside, with Rouhani solemnly kissing Khamenei's forehead as he lay in bed wearing a blue gown with his eyes closed but still wearing his spectacles.
Monday's announcement was the first time that official information has been given on Khamenei's health. In recent years, there have been widely circulated rumours that he had prostate cancer.
Such speculation grew during periods of silence from Khamenei but in recent weeks the leader has made numerous speeches and public appearances.
He was particularly vocal this summer in condemning Israel's military action in Gaza, which he described as genocide. He has also regularly lambasted the United States with whom Iran's relations have long been close to zero but which were hoped to improve following Rouhani's election last summer.  
Before being appointed as head of state 25 years ago, Khamenei served as president for almost eight years during the Iran-Iraq war.
Iran's Assembly of Experts, comprised of 86 religious figures elected by the people, is responsible for appointing the supreme leader and monitoring his actions. The supreme leader is appointed to an indefinite term but the assembly has the power to dismiss him.
The group met in Tehran last week but its president, Ayatollah Mohammad Reza Mahdavi Khani, an 83-year-old cleric, was absent due to his ill-health. He is in a coma and has been hospitalised since June 4 after suffering a stroke.
Khamenei's powers in military matters are particularly important, as he can pronounce peace or declare war by mobilising the armed forces of which he is effectively commander-in-chief.
As supreme leader, he also has direct control of the regime's media apparatus through state television and radio and thus he would have taken the decision to publicise his surgery.