XI'AN - China will invest 600 million yuan ($94.9 million) over the next three years to protect Hongjiannao Lake, the country's largest desert freshwater lake, from shrinking, local authorities announced Tuesday.

Hongjiannao was recently included by the Ministry of Finance on a list of national lake preservation projects, according to the lake management committee.

The ministry and the local government will allocate 100 million yuan respectively to the scheme annually.

The lake, sandwiched between the Muus Desert in Shaanxi province and the Erdos Plateau in Inner Mongolia autonomous region, has shrunk by over 40 percent in the past 15 years.

It covered 7,000 hectares in 1996, but has shrunk to 4,000 hectares, and its water level is declining by 60 cm annually, data from the lake's management committee showed.