Chinese Premier Li Keqiang on Sunday warned against U.S. President Donald Trump's "America First" policy, amid concern that Washington's economic protectionism will take a toll on the Asian country's economy.

"We will firmly uphold the rule-based multinational system," Li said in a speech at a reception held at Beijing's Great Hall of the People to mark the Oct. 1 National Day.

China "will open up at a higher level, and share development opportunities and outcomes with all other countries while upholding our own development interests," Li added.

The premier also expressed eagerness to promote Beijing's "One Belt, One Road" cross-border infrastructure initiative.

China has sought to expand its infrastructure networks in Asia, the Middle East, Europe and Africa to attain its goal of connecting countries situated along the ancient Silk Road more closely.

Beijing, meanwhile, has been engaged in tit-for-tat tariff hikes with the United States, sparking fears that a possible downturn in world trade dragging down China's economy, which has been buoyed by export growth.

China on Tuesday voiced unwillingness to hold talks with the United States toward the resolution of an escalating trade war as long as Washington continues to step up tariff measures.

Last Monday, the United States invoked tariffs on an additional $200 billion in Chinese imports. With the latest round of tariffs, Washington is now taxing around half of the products it imports from Beijing each year.

China immediately took retaliatory action, slapping additional tariffs on $60 billion in U.S. imports, meaning that Beijing has so far levied tariffs on more than 80 percent of all goods from Washington, together with the previous ones.

The United States and China have already imposed tariffs on a total of $50 billion of each other's products -- $34 billion in July and $16 billion in August. The U.S. tariffs were in response to China's alleged intellectual property and technology theft.