MOSCOW, Sep 13 (Reuters) - Russia's Vladimir Putin and China's Xi Jinping will discuss Ukraine and Taiwan at a meeting in Uzbekistan on Thursday (Sep 15) which the Kremlin said would hold "special significance" given the geopolitical situation.

Xi will leave China for the first time in more than two years for a trip this week to Central Asia where he will meet Putin, just a month before he is set to cement his place as the most powerful Chinese leader since Mao Zedong.

"The presidents will discuss both the bilateral agenda and the main regional and international topics," Kremlin aide Yuri Ushakov said at a briefing in Moscow.

"Naturally, they will give a positive assessment of the unprecedentedly high level of trust within the bilateral strategic partnership," he added.

The deepening "no limits" partnership between the rising superpower of China and the natural resources titan of Russia is a geopolitical development the West is watching with anxiety.

The meeting will give Xi an opportunity to underscore his clout while Putin can demonstrate Russia's tilt towards Asia; both leaders can show their opposition to the United States just as the West seeks to punish Russia for what Moscow calls a "special military operation" in Ukraine.

China is Russia's largest buyer of oil, one of the key sources of revenues for Moscow's state coffers.

Russia is also striving to boost its gas sales to China and build new pipelines to the country as its gas supplies to Europe have been significantly curtailed amid the stand off over Ukraine.

Ushakov said Moscow values China's position towards what he called the "Ukraine crisis", saying Beijing had struck a "balanced approach" towards the conflict.

China "clearly understands the reasons that forced Russia to launch its special military operation. This issue, of course, will be thoroughly discussed during the upcoming meeting," Ushakov said.

The meeting between Xi and Putin in Uzbekistan will take place on the sidelines of the Shanghai Cooperation Organisation's summit in the ancient Silk Road city of Samarkand in Uzbekistan.

Ushakov said no new energy deals with China are expected to be signed in Uzbekistan.