Belarus' largest electricity substation contracted by Chinese State-owned enterprise North China Power Engineering Co Ltd was put into operation on Monday, which analysts said was the biggest power grid cooperation so far between China and Belarus.

The 330-kV Pastvy substation, located in the northern state of Pastvy, will deliver 110 kV of power to the states of Grodno, Vitebsk and Minsk. It will also play a significant role for Belarus' first nuclear power plant, which is due to be completed by 2020.

"The cooperation between the two countries in energy is quite promising and we hope to continue our cooperation with NCPE in other projects," said the Belarus Minister of Energy Vladimir Potupchik.

Analysts said energy cooperation between the two countries has been fruitful in recent years, with $2 billion in energy projects taking up a considerable proportion of China's total investment in Belarus.

The cooperation is in accordance with Chinese companies' strategy of going global and the Belt and Road Initiative, and the Chinese power groups are also trying to diversify their earnings sources, according to Joseph Jacobelli, a senior analyst of Asia utilities at Bloomberg Intelligence.

These investments are unlikely to slow down in the future, he said.

China sees Belarus as an important partner in Belt and Road development, while President Xi Jinping urged more efforts to deepen trade and investment cooperation between the two countries during the Belt and Road Forum for International Cooperation in May.

The Pastvy substation connects the first nuclear power station in Belarus and the Ignalina Nuclear Power Station in Lithuania, according to NCPE.

As the only junction between the two nuclear power stations, the substation is responsible for transmitting the electricity generated from the Belarusian nuclear power station and distributing the electricity to some areas of Belarus, it said.

The Chinese engineering company, which is affiliated to China Power Engineering Consulting Group Co Ltd under China Energy Engineering Co Ltd, is also the prime contractor of Belarus' power grid renovation project for its nuclear power output.

The project, which kicked off in 2014, will cross three states of Belarus and cover over 60 percent of the area of the country. It will play an important role in nuclear power transmission and grid upgrading in Belarus.

The Belarus nuclear power transmission and grid connection project is the first project in Belarus using a Chinese government concessional loan from the Export-Import Bank of China and is also the largest transmission project constructed jointly by China and Belarus.