By ZHANG YUNBI in Beijing and ZHOU HUIYING in Harbin |

chinadaily.com.cn |

Visitors talk during the 10th China-Russia Expo, which opened on Sunday in Harbin, the capital of Heilongjiang province in Northeast China. With a total exhibition area of 55,000 square meters, the five-day event has attracted more than 1,500 companies from 46 countries and regions. WANG JIANWEI/XINHUA

President Xi Jinping and Russian President Vladimir Putin have each sent a congratulatory letter to the 10th China-Russia Expo ahead of the Russian leader's upcoming state visit to China.

The expo opened on Sunday in Harbin, the capital city of Heilongjiang province in Northeast China.