SHANGHAI - Premier Li Qiang on Sunday vowed efforts to further expand opening up and share China's development opportunities with the rest of the world.

Li made the remarks during his keynote speech at the opening ceremony of the sixth China International Import Expo (CIIE) and the Hongqiao International Economic Forum in Shanghai.

Chinese President Xi Jinping has sent a letter to the expo, reiterating China's firm determination to advance high-standard opening up and facilitate the building of an open world economy.

China will continue to promote opening-up with greater market opportunities, Li said, adding that China has a population of over 1.4 billion people and a middle-income group of over 400 million people, presenting huge potential in terms of market demand.

Noting that China has always been willing to share its market opportunities, Li said the country will actively expand imports, promote coordinated development of trade in goods and services, implement negative lists for cross-border service trade, support innovation in foreign trade formats and models, and boost digital trade.

China's imports of goods and services are expected to reach $17 trillion in cumulative terms in the next five years, according to him.

The premier also vowed that China will continue to ease market access and implement policies to remove all restrictions on foreign investment's access in the manufacturing sector.

China will protect foreign investors' rights and interests in accordance with the law, and continue to provide a business environment that is market-oriented, law-based and up to international standards, Li said.

In his speech, he reiterated China's commitment to pushing forward opening up with stronger innovation momentum.

"China is willing to step up cooperation with all countries in innovation, facilitate the deep integration of science and technology with the economy, promote the sharing of innovation results, and strive to remove barriers that hamper the flow of knowledge, technology, talent and other factors of innovation," Li said.

China will continue to promote greater inclusiveness and sharing of opening up, Li said, adding that the multilateral trading system with the World Trade Organization (WTO) at its core is the cornerstone of economic globalization and free trade, as well as an important guarantee for the steady recovery of the world economy.

China will always stand on the right side of history, follow the logic of progress of the times, firmly oppose unilateralism and protectionism, resolutely uphold the authority and effectiveness of the multilateral trading system, fully and deeply participate in the reform of the WTO and promote the early entry into force of the Investment Facilitation for Development agreement, he stressed.

The premier hailed the CIIE as "a big platform full of opportunities."

In the previous five editions, 131 countries and international organizations participated in country exhibitions, with nearly 2,000 new products, technologies and services making their debuts and a total intended turnover reaching nearly $350 billion.

U.S. companies have ranked first in terms of exhibition area at the CIIE for several years in a row, Li said.

Li revealed that over 3,400 exhibitors have registered for the event this year, among whom over 200 have participated in the CIIE for six consecutive years.

As the global economic recovery lacks momentum, he called for joint efforts to contribute to an open world economy. "We sincerely hope to work with other countries to make efforts in the same direction and make mutual achievements on a grand stage of openness."

Foreign leaders at the opening ceremony believed that the CIIE has become a key platform for global economic and trade cooperation, revealing China's commitment to deepening reform and expanding opening up as a major country.

They are willing to work with China to further strengthen cooperation in trade, investment, science and technology, infrastructure, e-commerce, health and other fields, promote the development of the Belt and Road Initiative, firmly support free trade and the WTO's authoritative role, continue to liberalize and facilitate trade and investment, and stabilize global industrial and supply chains to achieve inclusive and sustainable growth in the world.