Inner Mongolia's coal output reached 782 million tonnes last year, making it the nation's largest coal-producing region for a second year running, local authorities said Friday.

The output accounted for about 24 percent of China's total and was higher than neighboring Shanxi Province's 741 million tonnes, the coal mine safety administration in the northern autonomous region said in a statement.

Inner Mongolia, with the country's largest proven coal reserve of 732.3 billion tonnes, has set an annual production target of 880 million tonnes for this year.

It saw its coal output soar from 114.5 million tonnes in 2002 to 637 million tonnes in 2009, overtaking China's decades-long biggest coal producer Shanxi.