Tehran (AFP) - A plane carrying UN medical experts and aid touched down Monday in Iran on a mission to help it tackle the world's second-deadliest outbreak of coronavirus as European powers said they would send further help.

As the official death toll rose by 12 to 66, the Islamic republic turned down a similar offer from arch-enemy Washington, dismissing it as "propaganda".

The World Health Organization said a flight arrived from Dubai carrying medical supplies and experts on a fact-finding mission and to "provide guidance on strengthening and scaling up the response to the ongoing outbreak."

Germany, France and Britain, for their part, said they would send emergency medical supplies including testing equipment, body suits and gloves as well as five million euros ($5.5 million) to help tackle the outbreak.

Iran's confirmed cases leapt Monday by 523 on the previous day, hitting 1,501, said Deputy Health Minister Alireza Raisi.

State news agency IRNA reported the death of Mohammad Mirmohammadi, 72, a member of the Expediency Council which advises Iran's supreme leader Ayatollah Ali Khamenei.

It did not specify the cause of death but said he had died at Tehran's Massih Danechvari Hospital, the capital's main centre for coronavirus patients.

The outbreak that originated in China has sparked concern among Iran's neighbours, with the Gulf Arab states confirming 130 cases including, on Monday, Saudi Arabia's first case.

The health ministry in Riyadh, another key rival of Tehran, said the man had tested positive after returning from Iran.

Many of the Gulf's other victims are pilgrims returning from Iran, especially the Shiite holy city of Qom where the country's first case was reported.

US President Donald Trump had Saturday offered: "If we can help the Iranians with this problem, we are certainly willing to do so... All they have to do is ask."

But Tehran rejected the offer, charging that Trump, who has heaped sanctions and a campaign of "maximum pressure" on Iran, was offering help "for propaganda purposes".

"We are suspicious of the intentions of the Americans and do not count on this aid," said foreign ministry spokesman Abbas Moussavi, quoted by IRNA.

Germany, France and Britain, who remain as signatories to a 2015 nuclear deal with Iran despite Trump's withdrawal, expressed "their full solidarity with all impacted by COVID-19 in Iran".

Beijing, also a signatory to the nuclear deal, said an expert team from China had arrived Saturday in Tehran "to provide what assistance it can in terms of epidemic prevention and control and medical relief".

- 'Supplies running low' -

The WHO said it had sent Iran "medical supplies and protective equipment to support over 15,000 health care workers, as well as enough laboratory kits to test and diagnose nearly 100,000 people".

As the goods worth more than $300,000 -- including gloves, surgical masks and respirators -- were loaded onto an Emirati transport plane in Dubai, WHO's Robert Blanchard warned that global supplies were running low.

"What we see now is that demand has greatly exceeded our available stocks... and we are struggling to get access to more supplies."

The six-member medical team is made up of doctors, epidemiologists and laboratory specialists to help Iran detect and control the virus, Blanchard said.

WHO operations manager Nevien Attalla said the supplies were the "first big shipment which supports the response to coronavirus".

"Iran is a challenging country. You don't have always easy approvals to go," she said.

The UAE provided the military transport plane for the flight despite having downgraded its relations with the Islamic republic amid fierce rivalry between Iran and close UAE ally Saudi Arabia.

Gulf states have announced a raft of measures to cut links with Iran to curb the spread of the virus, cutting off transport links and telling citizens not to visit.

"Aid should reach all people regardless of their background," said Sultan Mohammed al-Shamsi, the UAE's undersecretary for humanitarian affairs.

IRNA reported the death of Mohammad Mirmohammadi, 72, a member of the Expediency Council which advises Iran's supreme leader Ayatollah Ali Khamenei.

It did not specify the cause of death but said he had died at Tehran's Massih Danechvari Hospital, the capital's main centre for patients suffering from the new coronavirus.

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