President Xi Jinping and Tajikistan's President Emomali Rahmon of Tajikistan saw the start of work on the China-Central Asia gas pipeline's Line D construction on Saturday in Tajikistan.

The project is a major stage of another important energy channel for the world's second-largest economy.

"The China-Central Asia gas pipeline project, which involves multiple participants, will significantly boost the regional economic development," Xi said during the ceremony.