A conservation group said Tuesday that the Arab world should offer more natural sites for the U.N.’s World Heritage register after having only two new ones recorded 15 years ago.

The International Union for Conservation of Nature said in a report that the Middle East and neighbouring territories have the fewest natural World Heritage sites. Only four are listed, featuring Ichkeul National Park in Tunisia, Banc d’Arguin National Park in Mauritania, the Wadi Al-Hitan in Egypt, and the Socotra Archipelago in Yemen.

Jordan has suggested the Wadi Rum protected designation zone as a natural and cultural site at the meeting of the World Heritage committee in Paris, which runs until June 29. It is one of 37 sites up for designation.

The study also found out that the 18-state zone does far less to direct and promote natural sites like desert landscapes and marine reserves than for cultural sites like pyramids and ancient fortifications. The report found that 12 states had 35 sites which have prospective to be listed but so far haven’t been nominated.

It found that 91% of states had inventories of cultural sites but nothing similar for natural sites. Also, cultural institutions in these countries “were not well equipped” to manage natural sites, and environmental ministries have often been locked out of the nomination procedure.

The report also reviewed management of natural sites that are already on the World Heritage List and found many face significant challenges.