Japan's Environment Ministry has decided to allow drivers to park their eco-friendly vehicles at some national parks and gardens for free, starting in April.

The ministry made the decision as part of its effort to promote vehicles that do not emit carbon dioxide.

Officials say the free parking will be available for electric and fuel cell vehicles at 16 parking lots in 10 national parks and two national gardens.

The two national gardens are Shinjuku Gyoen National Garden in Tokyo and Kyoto Gyoen National Garden. The national parks include Akan-Mashu National Park in Hokkaido and San'inkaigan National Park in Tottori.

The officials say the parking lots at the 10 national parks can be used for free all day.

But they add the free parking will be limited to two hours at most at Shinjuku Gyoen and to three hours at Kyoto Gyoen, as those national gardens are located at the center of each city.

The Japanese government seeks to achieve a carbon-neutral society. But the number of electric and fuel cell vehicles sold in Japan is much smaller than the figures for Germany and China.

The Environment Ministry has already launched a new program to double the amount of subsidies for purchases of electric vehicles, on condition that people have a facility to charge their cars with electricity that comes from renewable energy sources.