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Economic and political ties between China and Uzbekistan are stronger than ever. Our reporter Han Peng is in the capital Tashkent and explains how the two countries have elevated their ties during President Xi's visit and how the Silk Road Economic Belt initiative is also gaining momentum.

It’s the longest railway tunnel in Central Asia. The journey from Uzbekistan's capital Tashkent to its southeastern regions has now been reduced from four days to four hours.

"The tunnel is impressive. In the past, trains traveling southeast had to first go to another country, Tajikstan, in order to get around the high mountain," said Uzbek resident.

The 20-kilometer-long tunnel was built in three years by a Chinese company, the China Railway Tunnel Group. Along the way, engineers faced challenging geological hurdles including spontaneous fractures of rock.

"Rock burst is like a hidden bomb that might explode at any time and any place. When it happens, rocks and stones would splash all over the place. What's worse, there is still no technology to accurately predict the time, place or magnitude of the burst," said Zhou Xiaoguang, Project Manager of China Railway Tunnel Group.

The 450-million dollar project was largely paid for with loans from China. It’s the first step toward building what President Xi Jinping describes as "a logistic corridor from the Pacific to the Baltic Sea."

"The world's major commercial banks will seldom give loans to these countries, because they can hardly pass the rigid risk assessment. China's Import and Export Bank is more flexible, because it’s a state-owned, policy-oriented bank, which does not aim for short-term returns," said Liu Liang, chairman of Import-Export Bank of China.