But the full-on trade war failed to spook financial markets.
But what's clear is that the latest fight in the escalating trade war is likely, one way or another, to affect consumers, companies, markets, the economy and the political landscape. China has also pledged to buy soybeans from other countries, but replacing voluminous American supplies will be hard.
"But we have to do something", he added.
China has made a decision to slap levy on almost everything it imports from the United States in the ongoing tit-for-tat tariff war with the US.
But, it added "the likelihood of de-escalation will rise over time as the increasing economic impact in the USA will make the Trump team less combative, and China realises that it will be hard to integrate more into the global economy without some concessions regarding its specific economic model".
Meanwhile Beijing's plans for tariffs on $60 billion of US goods include an additional 5 percent duty on about 1,600 kinds of USA products including smaller aircraft, computers and textiles, and an extra 10 percent on more than 3,500 items including chemicals, meat, wheat, wine and LNG.
President Donald Trump on Tuesday defended the latest trade move against Beijing.
The threat of tariffs, Trump has said, should pressure Beijing to change its ways.
China remains unafraid of the "extreme measures" taken by the United States, the People's Daily newspaper said in a front-page article in its overseas edition on Wednesday.
In a wide-ranging speech, China's premier, Li Keqiang, sought to de-escalate the conflict by pledging significant further Chinese reform, including tax cuts, a commitment not to engage in competitive currency devaluation to boost exports, treating foreign firms equally with domestic ones, and a further crackdown on intellectual property theft.
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But the reality is that against a top side, you can lose and we have lost by a small margin. "You think that if you do well, you can get points against these teams".
But China will not resort to large scale stimulus to prop up the economy, he pledged.
What does China do next?
In June, the Trump administration said talks to change China's trade behavior - which had spanned decades - were going nowhere and announced duties on US$50 billion worth of Chinese imports. But its options for responding further are getting increasingly complicated.
Trump has promised that if China does retaliate, then he will not hesitate to slap tariffs on an additional $267 billion of Chinese goods. The administration is targeting a bewildering variety of goods - from sockeye salmon to baseball gloves to bamboo mats - forcing USA companies to scramble for suppliers outside China, absorb the import taxes or pass along the cost to their customers.
The latest United States duties spared smart watches from Apple and Fitbit and other consumer products such as baby auto seats.
This week, Washington raised the stakes by saying it would impose new tariffs on $200bn (£152.1bn) worth of Chinese goods from Monday. The tariff range of 5% to 10% is lower than the 5%-to-25% range China had threatened in early August.
Beijing will impose levies on a total of 5,207 USA products - ranging from liquefied natural gas to certain types of aircraft as well as cocoa powder and frozen vegetables - at 5 and 10 percent, instead of previously proposed rates of 5, 10, 20 and 25 percent, the finance ministry said.
"China has been unable to match the USA dollar-for-dollar in this round of tariffs, so a key question is what other steps China might take", Mark Williams, chief China economist at research firm Capital Economics, wrote in a note. And since China's economy is a state-directed capitalist-communist hybrid, they could go hammer and tongs at American interests through regulations.
China has dismissed the accusations and stood firm against USA pressure.
Last week, the American Chambers of Commerce in China and in Shanghai reported 52 percent of more than 430 companies that responded to a survey said they have faced slower customs clearance and increased inspections and bureaucratic procedures.