HOUSTON, July 18 (Xinhua) -- When national governments of the United States and China are working through some rough patches in their relationship, city-to-city and people-to-people relationships have become exceedingly important, vice chairwoman of the Sister Cities International (SCI) told Xinhua in a recent interview.

"Whether it is trade or intellectual property ... our governments will work out these issues. But what's most important is maintaining the friendships between our people," said Carol Robertson Lopez on the sidelines of the fourth U.S.-China Sister Cities Mayors' Summit here on Wednesday.

The summit was co-sponsored by the Chinese People's Association for Friendship with Foreign Countries and the SCI, a U.S. organization dedicated to promoting friendship with foreign cities. It gathered some 200 representatives to discuss topics such as innovation and smart cities, the maritime silk road, metroplex collaboration and Sino-foreign education exchanges.

This year marks the 40th anniversary of the establishment of U.S.-China diplomatic ties and over 200 cities from the two nations have celebrated their sisterships "with dancers, with music groups, and most importantly, youth exchanges," said Lopez.

Serving the SCI and formerly as a mayor of Santa Fe, capital of the New Mexico State, Lopez said she enjoys receiving delegations from around the world, including the Chinese delegates who came here to "experience America," since such trips can help them eliminate stereotypes of the destination countries and the people there.

"Until we've actually been to China or to the United States, we really don't know the character of the people. But when we get on ground and meet people and find out all we have in common, friendship grows," she said.

Noting that people across the world want the same things -- good education for their children, good jobs and good health care, Lopez said "it's our governments that sometimes have to work through some rough edges ... We can continue to maintain good friendships through mutual respect and cooperation."

As to the summit, Lopez said that cities are "renewing" friendships here, and reminding themselves of the vital importance of maintaining such friendships particularly when their national governments are working through issues.

A number of American and Chinese cities are here for knotting new sisterships and expanding links. An "economic matchmaking" event on Thursday and Friday will enable Texas companies to meet their Chinese counterparts and authorities for new economic opportunities, she said.

The former Santa Fe mayor thinks highly of the importance for U.S. cities to reach out to their Chinese counterparts, because "the economy is a worldwide economy" and no city can develop in isolation.

"If you go from state to state, you'll find businesses that are thriving because of their relationships with China and being able to export," she said.

She recalled a recent conversation she had with an economist, where they marveled at "all the right steps" that China took to become the "huge economic force" today. "It's hard to believe that in 40 years what China has done."

Having traveled to China six times, she noticed the progress China made in combating air pollution, saying that it is an example of China's resolve and ability to fix problems.

Lopez said the elementary and high schools in her city are now teaching Mandarin, hoping for the students to partner with those from Zhangjiajie, Santa Fe's sister city in China despite the distance.

She noted that people-to-people exchanges among the youth carry huge significance to the understanding between the two nations. "Our youth of today really are global citizens. They feel they're parts of the world," Lopez said.