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The leaders of China, Russia and Mongolia have signed a development plan to build an economic corridor linking the three neighbors. The plan pledges to boost transportation connectivity and economic cooperation in border regions.

Chinese President Xi Jinping (C), Russian President Vladimir Putin (L) and Mongolian President Tsakhiagiin Elbegdorj (R) attend the third trilateral leaders' meeting of the three countries in Tashkent, Uzbekistan, June 23, 2016. (Xinhua/Li Tao)

The agreement was signed after a meeting of leaders from the three countries ahead of the annual Shanghai Cooperation
Organization summit.

The idea was first floated in 2014 when President Xi Jinping proposed connecting China's Silk Road Economic Belt with Russia's transcontinental rail plan and Mongolia's Prairie Road program. The proposal was put into action last year when Mongolia's first highway program started.

Land-locked Mongolia will become a transit corridor linking China and Russia.

Chinese President Xi Jinping (C, front), Russian President Vladimir Putin (L, front) and Mongolian President Tsakhiagiin Elbegdorj (R, front) attend the third trilateral leaders' meeting of the three countries in Tashkent, Uzbekistan, June 23, 2016. (Xinhua/Li Tao)