China has replaced its deputy chief envoy to the long-stalled talks on North Korea's nuclear weapons program, a diplomatic source said Monday, in an apparent regular reshuffle of positions.

Xiao Qian, who assumed the role in May last year, was promoted as the director-general of the Asian affairs department at China's foreign ministry, the source said on the condition of anonymity.

"The successor (of Xiao) has been named, but no formal appointment has been made yet," the source said, without going into details about the successor.

Until the formal appointment is made, Xiao will temporarily double as the deputy chief envoy to the six-party talks on North Korea's nuclear weapons program, according to the source.

Xiao, a career diplomat who has worked in India, the United States and the Philippines, has served no positions in either South Korea or North Korea.

The six-party talks, involving South Korea, North Korea, the U.S., China, Russia and Japan, have been dormant since late 2008.

International sanctions on North Korea were tightened in early March following the North's fourth nuclear test in January and launch of a long-range rocket in February. (Yonhap)