DUBAI (Reuters) - Fifteen aid groups on Wednesday called on warring parties in Yemen to reopen the country’s main airport, saying a year-long closure was hindering aid and preventing thousands of patients from flying abroad for life-saving treatment.

FILE PHOTO: Houthi militants ride on a vehicle on the runway of the international airport of Yemen's capital Sanaa May 5, 2015. REUTERS/Khaled Abdullah

Yemen has been torn apart by a civil war in which the exiled government of President Abd-Rabbu Mansour Hadi, backed by a Saudi-led military coalition, is trying to push back gains made by the Iran-aligned Houthi group.

The Houthis control most of the north, including the capital Sanaa and its international airport while the Saudi-led coalition controls the airspace. Any reopening would need an agreement between the two sides, which blame each other for Yemen’s humanitarian disaster.

“The official closure of Sanaa airport, one year ago today, effectively traps millions of Yemeni people and serves to prevent the free movement of commercial and humanitarian goods,” the statement signed by groups including the International Rescue Committee and the Norwegian Refugee Council said.

Yemen has had more than 400,000 suspected cases of cholera in the past three months in an epidemic that has killed 1,900 people, the World Health Organization said in late July.

The aid groups said: “The current cholera outbreak and near-famine conditions in many parts of Yemen make the situation far worse. The importance of unhampered delivery of humanitarian aid cannot be overstated.”

Yemen’s health ministry estimates that 10,000 Yemenis have died from critical health conditions for which they were seeking international medical treatment, the statement said, adding it was unable to verify the figure.

It said this was roughly equivalent to the number of people that have died as a direct result of the fighting and represented the hidden victims of the conflict.

Citing United Nations figures, the statement said an estimated 7,000 Yemenis had gone abroad from Sanaa each year for medical treatment before the conflict. Now the number needing life-saving healthcare was around 20,000 Yemenis over the past two years because of the violence, it said.

“Yemenis awaiting critical medical treatment abroad now have to find alternative routes to leave the country, which include a 10-20 hour drive to other airports, often through areas where active fighting takes place,” the statement added.