Geologists have discovered a large gold deposit worth a potential 6.46 billion US dollars in northwest China's Xinjiang Uygur Autonomous Region, local officials said on Tuesday.

With at least 127 tons of proven reserves, it is the largest gold deposit ever discovered in resource-rich Xinjiang.

It is located in Uqar County, which borders Kyrgyzstan in west Xinjiang, according to the regional bureau of geology and mineral exploration and development.

"It's expected the total reserves will exceed 200 tons," said Cui Hongbin, head of the exploration team.

The discovery will not only increase China's gold output, which totaled 211.07 tons in the first half of this year, but will also benefit local revenue and employment, said Cui.

The bureau spent two decades exploring the area, where geological workers found more than 20 belts of gold ore in the 20-square-km Sawayaerdun deposit, he said.

The discovery has attracted the attention of several major mine developers in China who have expressed interest in co-development.

In 2013, the bureau also discovered two gold deposits with proven reserves of more than 50 tons each in the counties of Xinyuan and Hejing.