Chinese President Xi Jinping has arrived in Kazakhstan, ahead of the second China-Central Asia Summit. His visit is seen as a signal of Beijing's growing influence in the region. Kazakhstan is the core country in China's Belt and Road Initiative. To China, Kazakhstan is strategically vital to its regional security and energy routes. It is a key oil and natural gas supplier for China and also a vital overland gateway for China-Europe freight. Tan Yew Guan reports.