Stressing that China's economy will keep growing at a "medium-high" pace in the coming years, President Xi Jinping has offered reassurance to global investors during his United States visit.

"China's economic fundamentals remain solid and will continue to maintain long-term steady growth," Xi told more than 30 executives from top Chinese and US enterprises in Seattle on Wednesday.

He delivered similar messages on several other occasions, including a welcome dinner in Seattle and an interview with The Wall Street Journal.

By growing at "medium-high" speed, an annual growth rate of around 7 percent, China's economy will remain an engine for global growth.

China is capable of hitting its economic targets, supported by pro-investment policies, a vigorous service sector and progress in industrial restructuring, said Li Pumin, secretary general of the National Development and Reform Commission, the country's top economic planner.

The economy also looks set to benefit from reforms to improve resource allocation and encourage mass entrepreneurship and innovation.

"In the medium and long term, China is well-equipped and able to grow steadily and healthily," Li said.

In the first half of 2015, China's GDP expanded by 7 percent, its slowest pace in nearly a quarter of a century but still standing out from other major economies.

As long as China keeps this up, the country can realize its goal of doubling national GDP and per capita income by 2020 from their 2010 levels.

That scenario is crucial to the future of the global economy, which is still struggling on the path of recovery from the financial crisis.

Sustained growth by China's economy at around 7 percent will do a lot to boost the world economy, considering the country's economic output is about twice the scale of Japan and quadruple that of India, said Bai Ming, an economist with the Ministry of Commerce.

As the world's second-largest economy, China's development benefits not just itself but also the world.

In 2014, Chinese firms investing abroad paid 19.2 billion US dollars in taxes to overseas governments. They hired 135,000 employees from developed countries, an annual increase of 33,000, Bai said.

China is also the world's biggest source of outbound tourists, with overseas spending by Chinese reaching 164.8 billion US dollars in 2014, four times the amount of 2008, according to China Tourism Academy.

Compared with previous double-digit expansion, medium-high growth could allow China's economy to become more sustainable and greener, contributing to the global efforts to fight climate change and environmental pollution.

China, the world's largest greenhouse gas emitter, unveiled new climate change goals in June, promising to cut carbon dioxide emissions per unit of GDP by 60 percent to 65 percent by 2030 from 2015 levels and achieve a peak in emissions around the same year.

The country's shift of focus to a more sophisticated business models will also help drive the world economy, by exploring new areas of growth, according to Bai.

Chinese economists and legislators have warned foreign investors to accept and adapt to the changes happening in China's business environment.

China can no longer afford reckless expansion as resource supply and the environment become strained and the external market is limited, Bai said, arguing that the economy will get healthier and stronger by transforming its industrial structure to make it higher-end, cleaner, more innovative and driven by domestic consumption.

"Foreign firms in China should catch up with the transition and upgrade their technologies and strategies in the country," he concluded.

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