Iran has sent five planeloads of food to Qatar, which is suffering shortages amid a regional blockade, BBC reported.
A number of nations, including Iran's major rival Saudi Arabia, last week cut ties with Qatar, accusing it of funding terrorism, charges it denies.
The land border with Saudi Arabia, through which 40% of Qatar's food comes, has been closed.
Qataris have been ordered to leave some of the blockading nations, but Qatar has said it will not follow suit.A spokesman for Iran Air, Shahrokh Noushabadi, told the Agence France-Presse news agency on Sunday: "So far five planes carrying perishable food items such as fruit and vegetables have been sent to Qatar, each carrying around 90 tonnes of cargo, while another plane will be sent today."
It is unclear whether the food is an aid delivery or a commercial transaction.
Iran Air posted a tweet of a shipment being loaded at Shiraz airport.
Mr. Noushabadi said deliveries would continue "as long as there is demand".
AFP also quoted the Tasnim news agency as reporting that three ships with 350 tonnes of food were also set to leave for Qatar.
Iran has also opened its airspace to Qatari flights, following airspace closures by Saudi Arabia, Bahrain and the United Arab Emirates.
Analysts say Qatar's positive relations with Shia-led Iran - Sunni-ruled Saudi Arabia's arch-rival for influence in the region - were one of the causes of the latest rift, and the latest shipments are unlikely to ease the tension.
Meanwhile Qatar said it would not retaliate after Saudi Arabia, Bahrain and the UAE last week ordered all Qatari citizens to leave within 14 days.
Some 11,000 people from the three nations are believed to be in Qatar.