On taking power, the Khmer Rouge spurned both the Western states and the Soviet Union as sources of support. Instead, China became Cambodia's main international partner. With Vietnam increasingly siding with the Soviet Union over China, the Chinese saw Pol Pot's government as a bulwark against Vietnamese influence in Indochina. Mao pledged $1 billion in military and economic aid to Cambodia, including an immediate $20 million grant. Many thousands of Chinese military advisors and technicians were also sent to the country to assist in projects like the construction of the Kampong Chhnang military airport. The relationship between the Chinese and Cambodian governments was nevertheless marred by mutual suspicion and China had little influence on Pol Pot's domestic policies. It had greater influence on Cambodia's foreign policy, successfully pushing the country to pursue rapprochement with Thailand and open communication with the U.S. to combat Vietnamese influence in the region.