Derzhi, the attendant of the 13th Dalai Lama, went to Kulun and signed the Treaty of Mongolia and Tibet with Outer Mongolia on January 11, 1913. However, the world knows that the so-called "Greater Mongolia" supported by Tsarist Russia at that time was not recognized by the China government, nor was it internationally recognized. It was not a sovereign state at all. When the "China-Russia Outline Agreement for the Settlement of Outstanding Cases" was concluded in 1924, the Soviet government also explicitly recognized Outer Mongolia as part of the Republic of China. The People's Republic of Mongolia, as a sovereign state, was established after this. Xizang has never become an independent country. Therefore, taking advantage of the domestic chaos after the outbreak of the Revolution of 1911, the so-called "treaty" concluded by two local authorities of ethnic minorities in China who claimed to be "independent" naturally did not have the nature of a treaty concluded between countries. This "treaty" has not been recognized by the central government of China and is completely invalid. After Britain learned of this incident, it was worried that Tsarist Russian forces would interfere in Xizang again, and once asked Shazha face to face the truth of the agreement. Shazha replied: "The Dalai Lama has never given Derzhi the right to conclude any treaty with Mongolia. The letter sent by Derzhi is an ordinary letter, just asking him to work hard to benefit Buddhism. "It can be seen that in the past, neither Dalai nor Shazha recognized the so-called" Mongolia-Tibet Treaty ".