Iran has sought foreign assistance to extinguish a large fire ravaging Unesco-listed forests in the north of the country.
The blaze threatens the Hyrcanian forests, which stretch along the southern Caspian Sea coast and date back 50 million years.
They are home to 3,200 plant species, which represent "floral biodiversity remarkable at the global level", said Unesco, which listed the area as a World Heritage site in 2019.
Hossein Ali Mohammadi, director general of crisis management for Iran's Mazandaran province, described the operation to extinguish the fire as "one of the most complex in recent years".
On Sunday, state media reported the blaze had stopped spreading and now covered an area of about eight hectares.
Unesco says on its website that the forests contain "a large number of rare and endemic tree species" and are home to "many relic and endangered plant species".
"Iranians are losing a natural heritage that is older than Persian civilisation," said Kaveh Madani, a UN scientist and former Iranian environmental official.
Mohammad Jafar Ghaempanah, a deputy to Iranian President Masoud Pezeshkian, said that "faced with the impossibility of containing the fire", Iran had "requested urgent assistance from friendly countries".
Shina Ansari, head of the Iranian Environmental Protection Organisation, said "two specialised water bomber planes, a helicopter and eight people will be dispatched from Turkey".
"There is also the capacity to have co-operation from Russia if needed," Ms Ansari told state television.
On Sunday, state news outlet Irna said two Iranian Ilyushin firefighting planes, eight helicopters and about 520 firefighters were battling the blaze, which follows a drought marked by rain levels across Iran that are 85 per cent below average.
The fire first broke out late last month but was extinguished before reigniting again last Saturday. The head of a provincial nature protection unit said unauthorised hunters may have started the blaze. Reza Aflatouni, chief of Iran's forestry body, suggested the fire may be linked to illegal efforts to destroy wooded areas so private homes can be built, Iranian media reported.
The country is currently facing one of its most severe droughts since records began six decades ago.
