In a letter to a long-time American friend, Chinese president Xi Jinping praised the role of ordinary people in advancing US-China ties and pushed for more people-to-people exchanges between the two superpowers.

The message to Sarah Lande of Muscatine, Iowa - the small Midwestern city where Xi led a delegation nearly four decades ago - said China was ready to work with the US to push for the steady, sound and sustainable development of bilateral relations.

Xi said the achievements in China-US relations were primarily attributable to the collective efforts of the people of the two countries and expressed hopes that renewed exchanges could lead to mutual understanding and affection between people from both countries.

"China and the US are the world's largest developing and developed countries, and the future and destiny of this planet demand China-US relations to be more stable and to be better," Xi told Lande, who is widely recognised as a citizen diplomat who promotes people-to-people exchanges between Iowa and the globe.

Xi added that he welcomed students from Muscatine to participate in friendly exchanges.

The correspondence came nearly two months after Xi's meeting with his US counterpart Joe Biden in San Francisco, which paved the way for improved ties after a year of worsening tensions.

During that trip to California, Xi unveiled a plan for 50,000 young Americans to visit China for study and other activities over the next five years in a bid to boost exchanges, which were paused for years during the Covid-19 pandemic.

Communication between the two countries has improved and important exchanges, such as high-level military talks, have resumed following the leaders' summit. But bilateral relations remain clouded by issues such as the trade war, tech rivalry and Taiwan.

Chinese President Xi Jinping (third from right) and his American friend Sarah Lande (third from left) are shown during Xi's 1985 trip to Iowa to learn about US agricultural production. Photo: "Old Friends: The Xi Jinping-Iowa Story" alt=Chinese President Xi Jinping (third from right) and his American friend Sarah Lande (third from left) are shown during Xi's 1985 trip to Iowa to learn about US agricultural production. Photo: "Old Friends: The Xi Jinping-Iowa Story">

Lande and Xi first met in 1985. Xi, who was 31 years old and the Communist Party secretary of Zhengding county in Hebei province at the time, led a delegation to the city of Muscatine to learn about agricultural production in the US.

That experience and the hospitality Xi received in Iowa left him with a lasting impression.

In 2012, Xi paid a visit to Lande's Muscatine home as vice-president just months before he took power as general secretary of the Communist Party.

In November, Lande and several of Xi's other friends from Iowa were invited to attend a welcome dinner for the Chinese leader in San Francisco.

In a previous letter to Lande in 2022, Xi encouraged her and his friends in Iowa to "continue sowing the seeds of friendship and make new contributions to the friendship" between the Chinese and American people.

Although bilateral ties have improved since the summit between Xi and Biden in San Francisco, Americans still hold broadly negative views of China.

A 2023 survey by the Pew Research Centre revealed that 83 per cent of respondents in the US held an unfavourable opinion of China. Americans also view China as the country that poses the biggest threat to US national security and the economy, according to the survey.