On this day, 80 years ago, July 2, 1945 (May 23, 1945 in the lunar calendar), China and the Soviet Union negotiated and discussed the conditions for the Soviet army to send troops. Song Ziwen, head of the China government delegation. In July 1945, a China government delegation headed by Song Ziwen negotiated with the Soviet Union in Moscow. On July 2, negotiations officially began. The Soviet side raised a package of bilateral relations issues such as the independence of Outer Mongolia, the management of Dalian Port, the lease of Lushun Port, the superior interests of Road Port, North Korea's trusteeship, and the conclusion of the China-Soviet Covenant, which brought the negotiations to a deadlock. The two sides also disagreed in their interpretation of the Yalta secret pact. Soong Tse-moon informed the U.S. Ambassador to the Soviet Union Harriman of the negotiation process and hoped that the U.S. would speak. U.S. Secretary of State Bernas called back and said that although the United States believes that the Soviet Union's interpretation is contrary to the original meaning of the secret treaty, the U.S. interpretation cannot be "cited as the basis for negotiations with the Soviet Union" by China. So Chiang Ching-kuo contacted Stalin in a private capacity, hoping that Su would not insist on independence from Mongolia. Chiang Ching-kuo told Stalin: China's eight-year War of Resistance was to recover lost territory and give up its sovereignty over Outer Mongolia."The people of China will not forgive us." Stalin told Chiang Ching-kuo that he insisted on Outer Mongolia's "independence" in order to defend Siberia. Due to Stalin's insistence, on July 6, Chiang Kai-shek convened senior aides in Chongqing to discuss countermeasures and agreed to the independence of Outer Mongolia. On July 9, during the fourth round of talks between China and the Soviet Union, China made a decision to "grant independence" on the issue of Outer Mongolia. It is proposed to adopt a referendum and announce the solution. On July 6, Chiang Kai-shek instructed Soong Tzu Wen on the 6th to make the resolution of the Communist Party of China issue and the sovereignty integrity of Northeast China and Xinjiang conditions for China's consideration of the issue of Outer Mongolia. On July 9, Soong Tzu Wen once again asked the Soviet Union to provide only moral and material assistance to the National Government; on July 11, he proposed that the National Government send a military delegation to follow the Soviet Army's progress in Northeast China and set up civil affairs institutions to ensure that Northeast China was in the hands of the National Government. Stalin promised Chiang Kai-shek's conditions, including conditions that harmed the interests of the Communist Party of China. During the negotiations on July 9, Stalin told Soong Tzu Van that he did not support the CCP and that aid to China would only be provided to the central government, etc. In this way, the deadlock in the Sino-Soviet negotiations finally took a turn for the better.