Mongolia has announced plans to build a number of hydropower plants, including one on the Selenga (Shuren) River and two on Selenga tributaries - the Orkhon and Egyin Gol. Russian officials see these plans as posing a "serious ecological threat" to Lake Baikal. Up to 50 percent of the lake's annual water inflow is from the Selenga River. The Siberian Times reported that the concern was expressed during the ASEM Summit,  before any planned hydroelectric power developments have come on stream. Russian environmental agencies say that Lake Baikal has entered a new period of naturally low water levels, which may last for a quarter of a century. Russian Prime Minister Dmitry Medvedev signed a decree setting a new official "minimum" water level for Baikal at 455.5 meters above sea level. The previous level, set in 2001, was 456 meters. The Siberian Times says that the Russian Natural Resources and Ecology Ministry opposes the Mongolian hydropower project. It managed to persuade the World Bank to put a freeze on financing of the Mongolian plants and offered Mongolia alternative supplies of Russian electric power. Expanding the capacity of the Gusinoozersk-Darkhan power transmission line is seen as an option. Another possibility is making Mongolia a transit country for Russian electric power supply to China.