Chinese Premier Li Keqiang said Friday China's opening-up policy will not change "just as the course of the Yangtze and Yellow rivers will not be reversed."

No matter how the international environment may change, China will keep the course of wider openness, Li told a press conference after the closing of the fifth session of the 13th National People's Congress.

"If there will be any change, the change will be conducive to China's greater openness to international exchanges, trade and investment," the premier said. "Anything that is conducive to expanding high-level opening-up, we will go for it."

China's economy has deeply integrated into the world, Li said. Imports and exports in goods contribute to more than one third of China's gross domestic product, and the country has remained the world's second-largest import market for 10 consecutive years. China has also been the largest trader in goods over the past five years.

As the economy is still climbing up the industrial chain, China has tremendous potential and broad space for the growth of all types of investment, the premier said, promising a level playing field for all types of businesses, no matter homegrown or foreign-funded.

As the Regional Comprehensive Economic Partnership agreement, the world's largest trade deal, has come into effect, China will seize the opportunity to push forward free trade and keep itself a popular destination for foreign investment, he said.

As more than 40 years of opening-up has brought mutual benefits to China and the world, Li described the policy as a "door of opportunity." China will not and must not close it, he added.