exceeding exports to the United States. With the huge increase in China-Saudi trade, Saudi Arabia has emerged as a significant investor in the PRC. Saudis are eager to invest in Chinese oil-industry related projects as a way to secure their status as a major oil provider to China. For example, in 2004, Saudi Arabia's Saudi Aramco Overseas Company invested nearly 1/3 of the $3 billion in funds needed for the construction of a petrochemical facility in China's southeastern Fujian Province, which is planned to process 8 million tons of Saudi crude oil. Upon completion of this project, the refinery would be able to refine triple its capacity and have the ability to process the Saudi "distressed" crude oil that otherwise could not be refined in China. Further, in 2006, the PRC and Saudi Arabia agreed to jointly construct an oil storage facility on China's Hainan Island and Saudi Arabia invited Chinese firms to participate in infrastructure development worth $624 billion. On April 6, 2012, SABIC announced a new investment plan of $100 million to set up a new technology center in the Kangqiao area of Shanghai. Three days earlier on April 3, SABIC launched the second phase of construction projects for petrochemical plants in the cities of Tianjin and Chongqing, which were part of the US$11 billion project with the state-run Sinopec Group to continue boosting output at polycarbonate production complexes. Besides oil-related companies, other major Saudi companies - such as the Saudi Arabian General Investment Authority (SAGIA) and Saudi Arabian Airlines have established offices in China. In 2006, Saudi Arabia invested $1.1 billion in China, the first significant investment since 2000. Likewise, in 2006, China's largest aluminum producer - Aluminum of China (Chalco) partnered with Saudi companies to build a $3 billion aluminum facility in Saudi Arabia. In 2009, China Railway Company won a $1.8 billion bid to build a monorail in Mecca as a way to help transport pilgrims. In May 2019, China's import of Saudi crude oil has increased by 43%. This has made Saudi Arabia the top supplier to China. Military relations While official diplomatic relations between Saudi Arabia and China were not established until the 1990s, defense relations began beforehand in the 1980s. When the United States refused to sell Saudi Arabia long-range fuel tanks for Saudi F-15 fighters, Prince Khalid bin Sultan traveled to China to purchase ballistic missiles. Saudi Arabia arranged a deal