Page "Treaty of friendship and alliance between the Government of Mongolia and Tibet" Paragraph 4

In any case, the independence of both Tibet and Mongolia continued not to be recognized by most other powers, which continued to recognize at least the suzerainty of the Republic of China over these areas.

Even Russia and the UK were more comfortable with formally recognizing China's suzerainty and keeping an ambivalent position towards Mongolia and Tibet's independence.

In addition, there was a concern among the Western powers ( again particularly Russia and UK ) that recognizing Tibetan or Mongolian independence would allow those areas to come under the other power's influence, respectively, a situation which all concerned believed to be worse than a situation in which those areas were nominally under the control of a weak China.