After visiting the US states of Illinois, Iowa and Minnesota from April 19 to 25, Chinese Ambassador to the United States Qin Gang said he felt confident about the future of China-US ties.

"I leave the heartland with my heart filled with friendship and cooperation and, more importantly, filled with confidence in the future of China-US relations," Qin Gang wrote in an article published by The Des Moines Register, an Iowa newspaper.

The stories of win-win cooperation and of friendship passed through generations, the common qualities of Chinese and Americans, and young people's respect and appreciation for each other's country and its culture had touched him during his visits, Qin said.

At the Kimberley family's farm in Maxwell, Iowa, Qin helped promote US beef and bacon in a livestream and tried his hand at driving a John Deere tractor. The Kimberley farm hosted President Xi Jinping during his visit to the US in 2012, when he was vice-president.

At the Zoetis Inc plant in Charles City, Qin learned that most of the plant's animal vaccine products are exported to the Chinese market.

At the Smithfield processing plant in Denison, Iowa, Qin and his team had lunch with the workers. They were told that the world's largest pork producer has created thousands more US jobs since its acquisition by a Chinese company.

Qin said that the journey had afforded the Chinese delegation a panoramic view of the whole industrial chain of US agriculture, from which they can see that US farmers and agricultural companies need China, benefit from China and look forward to further cooperation with China.

"China and the United States are natural partners for agricultural trade. With the Chinese market wide open, the two sides have broad space for further agricultural cooperation, and this is a call to action to create conditions for two-way, normal agricultural trade and lift the additional tariffs and other obstacles," he wrote.

"On top of that, our cooperation should not just be about 'buy and sell'; it can go deep into agricultural technology, climate action and sustainable development. Economic and trade ties, especially those in agriculture, are the ballast of China-US relations, and the American business community and farmers are the backbone of a stable China-US relationship－this trip has deepened my belief in this basic fact."

Qin and his team visited the Sino-US Friendship House in Muscatine, where Xi stayed during his visit to Iowa in 1985. They met with old friends Sarah Lande and Luca Berrone, who had welcomed Xi twice, and attended the signing ceremony for Chinese enterprises participating in a program to sponsor Iowa students who want to study in China.

"We could tell that the seeds of friendship first sown by President Xi have taken root, sprouted, blossomed and borne fruit in Iowa. We could also see from this experience that the bond between China and the United States is unbreakable, and such a bond is forged by all those people who champion the cause of China-US friendship and cooperation," Qin said.