The first regular cargo train linking southwest China's Chongqing Municipality and Duisburg in Germany departed in early April, marking the latest step in the two countries' building of a Silk Road economic belt.

China and Germany are at opposite ends of the Silk Road economic belt, trade infrastructure along a route linking east Asia and Europe through central Asia. They were called on to serve as engines for economic growth by Chinese President Xi Jinping during his visit last month to the port of Duisburg, the world's biggest inland harbor and a European transport and logistics hub.

The two countries, linked by the Chongqing-Xinjiang-Europe international railway, should strengthen cooperation in building the Silk Road economic belt, Xi said.

On the trip to Duisburg, he witnessed the arrival of a cargo train at the city's railway station from Chongqing. It had traveled the entire length of the Chongqing-Xinjiang-Europe international line.

This was launched in January 2011. A total of 110 customized trains, mostly loaded with electronic products, have traveled along the route so far. With the operation of the regular train, 114 trains are expected to exchange diversified products between the two countries within this year.

The railway begins in Chongqing, crosses the border into Kazakhstan at Alashankou, and passes through Russia, Belarus and Poland before reaching its terminus in Duisburg at the heart of Europe.

The railway cuts the five-week shipping time of the past to only about two weeks, and costs 80 percent less than air transportation.

"The Chongqing-Xinjiang-Europe international railway has boosted economic cooperation between all the countries along the route," said Soren Link, mayor of Duisburg.

According to China's Ministry of Commerce, the country's 2012 trade with all countries along the economic belt topped 549.5 billion U.S. dollars, accounting for 14.2 percent of its total foreign trade volume that year.

And the railway has also provided a great opportunity for the opening up of inland cities in China, according to Dai Dingyi, deputy head of the China Society of Logistics.

With the encouragement of the Chongqing-Xinjiang-Europe railway, more Chinese cities, including Zhengzhou in central China's Henan Province and Chengdu in southwest China's Sichuan Province, have launched railway lines to European cities.

In the past three years, high-tech companies including AT&S, Europe's largest printed circuit board (PCB) producer, have set up manufacturing bases in the city's Liangjiang New Area, the third national development zone in China.

In 2013, Chongqing attracted 10.6 billion U.S. dollars of foreign investment, and its total import and export volume reached 68.7 billion U.S. dollars.