Most of the patients to be flown out of the war-torn country are women and children who need urgent medical attention.
The United Nations is working to open a humanitarian air bridge to take Yemeni cancer patients for treatment at qualified facilities, World Health Organisation (WHO) country representative for Yemen Nevio Zagaria said on Sunday.
"The aim is to help patients suffering from cancer, chronic diseases and congenital anomalies receive the treatment they need," Zagaria said, adding that 12 health conditions had been targeted.
These include leukemia, cervical and thyroid cancer, and "patients who need... bone marrow and kidney transplants," said Zagaria of the World Health Organisation (WHO).
The air bridge will operate for an initial trial period of six months, WHO said, without specifying where the patients would be sent for treatment.
"Eighty percent of patients for this flight are women and children," Zagaria said, adding: "The air bridge is one of their last hopes."
Twenty-two million people, or three in four Yemenis, require some form of humanitarian assistance in the conflict-ravaged country.
The UN's Yemen envoy, Martin Griffiths, arrived Sunday in the rebel-held capital Sanaa.
He is pushing for new peace talks after a failed attempt to bring the two sides together in Geneva earlier this month.
Saudi Arabia and its allies intervened in 2015 in the conflict between embattled Yemeni President Abedrabbo Mansour Hadi, whose government is recognised by the United Nations, and the Houthis.
Nearly 10,000 people have since been killed and the country now stands on the brink of famine.