The governors of Yamanashi and Shizuoka prefectures have warned they might start charging an admission fee to visit Mount Fuji in a bid to finance environmental efforts on the iconic mountain.

Yamanashi Gov. Shomei Yokouchi said the two prefectures, whose borders are straddled by Japan's highest mountain, will jointly determine how much to charge and when to commence a fee-based system. An admission fee might be introduced on a trial basis at an early date, he added.

"It's likely we'll ask climbers to share certain burdens," Yokouchi told reporters Saturday, although Shizuoka Gov. Heita Kawakatsu said it's possible the prefectures will "start by collecting contributions rather than a compulsory charge."

The move comes at a time when Japan is hoping to have Mount Fuji listed by UNESCO as a World Heritage site.

The two prefectures have discussed the introduction of an admission charge for the last 15 years due to the degradation of Mount Fuji's environment from the volume of visitors and climbers. However, concerns that the plan could cause visitor numbers to tumble have hindered its implementation.

Yokouchi and Kawakatsu were attending an event in Tokyo organized to promote the mountain's bid for a World Heritage listing.