Trade volume between China and Cambodia exceeded $5 billion last year, but the potential for cooperation still needs to be further tapped, Cambodian Prime Minister Hun Sen said through an interpreter on the sidelines of the 15th China-ASEAN Expo on Tuesday.

It was Hun Sen's 11th visit to the China-ASEAN Expo. This year's event in Nanning runs from Sept 12 to 15. It was the second time for Cambodia to be the country of honor.

Hun Sen said he attached great importance to the expo because Cambodia, as well as ASEAN countries in general, benefit from the platform, as does China. It is a win-win event that broadens cooperation in all fields, he said.

"But we can obviously see that trade cooperation yielded more fruit for ASEAN countries than China, as ASEAN exports various kinds of agricultural and tourism products to China while it imports only a few," he said.

In 2017, trade volume between China and ASEAN reached $514.8 billion, a 13.8 percent increase over the previous year. The annual growth rate ranges from 10 to 25 percent, he said.

"So I think what Cambodia and other ASEAN countries should really do in the future is put aside controversy and concentrate on practical cooperation with China on the economy and technology so as to bring peace and prosperity to the community," he said.

This year marks the 60th anniversary of the establishment of diplomatic relations between Cambodia and China, and he said the relationship has come to a critical point as it moves into a comprehensive strategic partnership phase from good neighbor and even to "iron brother," as President Xi Jinping characterized it during his visit to Cambodia in 2016.

In Hun Sen's perspective, the "iron brotherhood" asks the two nations to deepen mutual trust by keeping their actions consistent with their words. Cambodia is sincere in its attitude toward China on diplomatic issues and is by no means pursuing an opportunistic foreign policy, he said.

"Nowadays there are solid political ties between us, but it's not enough for a sustainable relationship. We still have a lot to do to further deepen ties in investment, tourism and culture, for example, and to promote exchanges of youth by supporting more Cambodian students' studies in China," he said.

He put the number of Chinese tourists at 1.3 million last year and said it should reach 2 million this year.

"Cambodia has benefited a lot from its cooperation with China," he said. "And with the further implementation of the Belt and Road Initiative and 21st Century Maritime Silk Road, we can make a bigger difference in the future."