Chinese Premier Li Keqiang said Wednesday that the country's economy has entered a phase of medium and high rate growth, striking an optimistic tone of keeping stable and sustainable development.

During his speech at the opening ceremony of the World Economic Forum Annual Meeting of the New Champions 2013 in northeast China's Dalian, Li said a growth of around 7.5 percent is still considered high for any major economy in the world, although it is slower than the double-digit growth in the past.

China's economy had kept growing by nearly 10 percent annually in the past three decades until the global financial crisis snapped the red-hot speed four years ago.

Since then, the world's second largest economy has prioritized quality over speed in a bid to inject more sustainable and vigorous power to guarantee future growth.

The government targets an annual GDP growth of 7.5 percent for 2013.

"As the economy enters a phase of transformation, the slowdown of its prospective growth and moderation of the Chinese economy from a high speed to a medium to high speed are only natural." Li told the meeting.

"Now the new season of the Chinese economic miracle, one of better quality and higher efficiency, is unveiled," he noted.

China's future growth must be bolstered by resource conservation and environment protection, and driven by technological innovation and advance.

It has to be a growth with sufficient employment and growing household income, he added.

"Looking ahead, I see bright prospects for China's development," Li said.

The process of industrialization and urbanization is far from being completed in China, which promises a big room for regional development and huge market potential. Reform is bound to unleash fresh institutional vitality.

"We are well placed to sustain a healthy economic growth in the long run...And we will achieve the sustained and sound growth of the Chinese economy," he said.