Tehran announces Ramadan starts Wednesday in Iran
"The Ramadan month's crescent was not viewed at dusk on Monday," state news agency IRNA reported on Tuesday, referring to the search for a crescent moon that heralds the start of the holy month.
Therefore "Wednesday, the 25th of Farvardin, will be the first day of the blessed month of Ramadan," it added, quoting a statement from Ayatollah Ali Khamenei's office.
The start of Ramadan is set by both lunar calculations and physical sightings that determine when one month ends and another begins.
During Ramadan, observant Muslims refrain from eating and drinking from dawn to dusk, and traditionally gather with family and friends to break their fast in the evening.
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The holy month approaches as Iran is struggling to contain its "fourth wave" of Covid-19 infections and deaths, blamed by officials on a surge in trips made during last month's Persian New Year holidays.
Total cases have spiked above two million with overall fatalities at almost 65,000.
On Monday, the health ministry announced 23,311 new cases in 24 hours, a new daily infection record.
Health Minister Saeed Namaki on Monday urged the population to stay at home to pray. Group prayers should be held only once a day, "with a minimum number of people, in the open air, while observing maximum distance and using masks," he said.
Iran's President Hassan Rouhani, faced with a deep economic crisis, on Saturday announced "aid packages" for the month of Ramadan intended for "60 million people" out of Iran's estimated 83 million.