The presidents of China, Russia and Mongolia kicked off their first three-party summit on Thursday on the sidelines of the 14th summit of the Shanghai Cooperation Organization in Dushanbe, Tajikistan.

The leaders will discuss trilateral cooperation in the transportation, electricity, mining, environmental, healthcare, agricultural and other spheres, Russian President Vladimir Putin's aide Yuri Ushakov said on Wednesday.

"The Russian-Chinese-Mongolian top-level talks will be held for the first time and are expected to become regular in the future," ITAR-TASS quoted Ushakov as saying.

The rare meeting closely followed separate visits by President Xi Jinping and Putin to Mongolia.

Both Xi, in August, and Putin, in early September, witnessed a number of agreements with Mongolia, ranging from energy to infrastructure, during the visits.