Iran reacted angrily on Friday after US sanctions on air travel shut off a route to the holy Shiite city of Najaf in Iraq.
The Iranian Civil Aviation Organisation said ticket sales to Najaf had been suspended, as the effect of US sanctions ripples across the Middle East.
An Iranian consulate in the city expressed outrage at the ban. It wrote on X: "Najaf International Airport, the shrine of the first Imam of the Shiites, and the capital of their last Imam, is closed to the largest Shiite country in the world?!".
Najaf is home to the Shrine of Imam Ali, the Prophet Mohammed's cousin and son-in-law. In June, the coffin of Iran's late supreme leader Ayatollah Ali Khamenei was paraded in the city as part of a funeral detour in Iraq.
Flights to Baghdad were suspended on Wednesday. But Iranian state media had initially said that the route to Najaf would remain open.
The sanctions are part of the US campaign to isolate Iran economically and force concessions in the war. Treasury Secretary Scott Bessent said on Monday that companies who deal with Iranian airlines would be "knocked out of the dollar system".
Responding to the sanctions, the UAE on Thursday suspended all flights operated by Iranian airlines to and from the country until further notice. Flights between Iran and Oman have also been affected.
