Mogao Grottoes now has 735 grottoes,ranked as a UNESCO world cultural heritage site in 1987 more than 2,000 colored statues, and 45,000 square meters of frescos. (Xinhua File Photo)

China published a plan on Tuesday for the protection of Mogao Grottoes, one of the country's three major Buddhist art treasures, in Dunhuang city of China's northwest Gansu province.

The document, which took eight years to complete, was endorsed by the State Administration of Cultural Heritage before coming into effect Tuesday, said Fan Jinshi, curator of the Dunhuang Academy.

It was drafted by Chinese heritage preservation experts, with the help of specialists from the United States and Australia, he said.

The document has designated a 1,344-square km conservation area for heritage and environment protection.

"It's aimed at preserving and sustaining the treasures," said Chen Tongbin, head of the Institute of Architectural History under China Architecture Design and Research Group.

Chen and his colleagues began drafting the plan in 2003, shortly after a regional law was passed for the better protection of all underground relics, sites of historical interest and the natural environment around the Mogao Grottoes.

The Mogao Grottoes, or the Ancient Caves of 1,000 Buddhas, were listed in 1987 by the United Nations' Educational, Scientific, and Cultural Organization as China's first world heritage site.