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"In light of China's unfair retaliation, I have instructed the USTR to consider whether $100 billion of additional tariffs would be appropriate under section 301 and, if so, to identify the products upon which to impose such tariffs," Trump said in a statement.

President Donald Trump on Thursday said he has instructed the United States Trade Representative to consider $100 billion in additional tariffs against China.

U.S. President Donald Trump and China's President Xi Jinping leave a business leaders event at the Great Hall of the People in Beijing on November 9, 2017.

China on Wednesday announced it would introduce tariffs on 106 U.S. products, including soybeans, cars and whiskey.

The tariffs were introduced as a retaliatory measure against Trump, who, just 24 hours prior, had unveiled a list of Chinese imports he planned to target with tariffs. Some of Beijing's measures, experts said, were less about hurting the U.S. economy and more about hitting Trump politically by targeting elements of his base.

Trump's proposed tariffs include products used for robotics, information technology, communication technology and aerospace, areas in which Trump feels China could unfairly advance with the help of U.S. intellectual property.

Despite the severity of Trump's threats on Thursday, he emphasized that the U.S. is still open to negotiation concerning China's trade practices.

"The United States is still prepared to have discussions in further support of our commitment to achieving free, fair, and reciprocal trade and to protect the technology and intellectual property of American companies and American people," Trump said in a statement.

Shortly after Trump's announcement, U.S. Trade Representative Robert Lighthizer expressed support for the move, calling Trump's response "appropriate."

"President Trump is proposing an appropriate response to China's recent threat of new tariffs. After a detailed investigation, USTR found overwhelming evidence that China's unreasonable actions are harming the U.S. economy," Lighthizer said in a statement.

He also condemned China's retaliation and the harm it could cause American workers, farmers and businesses.

"The appropriate response from China should be to change its behavior, as China's government has pledged to do many times," he said in a statement.

"Unfortunately, China has chosen to respond thus far with threats to impose unjustified tariffs on billions of dollars in U.S. exports...Under these circumstances, the President is right to ask for additional appropriate action to obtain the elimination of the unfair acts, policies, and practices identified in USTR's report," he added.

Lighthizer emphasized that additional tariffs will not be implemented until they undergo a public comment process.

China, for its part, has taken a defiant tone to the White House's trade threats. In fact, Chinese state media has claimed victory in the trade dispute so far, saying Beijing's tariffs will hurt Trump voters.

"Trump has already proved himself wrong because China has demonstrated that it can't be coerced and is fully determined to reciprocate," an English-language editorial from China Daily said Thursday. "It's really time for Trump to give up the useless tariff weapon and come to the negotiation table."

Here are the statements from Trump and Lighthizer:

Statement from President Donald J. Trump on Additional Proposed Section 301 Remedies Following a thorough investigation under section 301 of the Trade Act of 1974, the United States Trade Representative (USTR) determined that China has repeatedly engaged in practices to unfairly obtain America's intellectual property. The practices detailed in the USTR's investigation have caused concern around the world. China's illicit trade practices − ignored for years by Washington − have destroyed thousands of American factories and millions of American jobs. On April 3, 2018, the USTR announced approximately $50 billion in proposed tariffs on imports from China as an initial means to obtain the elimination of policies and practices identified in the investigation. Rather than remedy its misconduct, China has chosen to harm our farmers and manufacturers. In light of China's unfair retaliation, I have instructed the USTR to consider whether $100 billion of additional tariffs would be appropriate under section 301 and, if so, to identify the products upon which to impose such tariffs. I have also instructed the Secretary of Agriculture, with the support of other members of my Cabinet, to use his broad authority to implement a plan to protect our farmers and agricultural interests. Notwithstanding these actions, the United States is still prepared to have discussions in further support of our commitment to achieving free, fair, and reciprocal trade and to protect the technology and intellectual property of American companies and American people. Trade barriers must be taken down to enhance economic growth in America and around the world. I am committed to enabling American companies and workers to compete on a level playing field around the world, and I will never allow unfair trade practices to undermine American interests.

USTR Robert Lighthizer Statement on the President's Additional Section 301 Action "President Trump is proposing an appropriate response to China's recent threat of new tariffs. After a detailed investigation, USTR found overwhelming evidence that China's unreasonable actions are harming the U.S. economy. In the light of such evidence, the appropriate response from China should be to change its behavior, as China's government has pledged to do many times. Economies around the world – including China's own – would benefit if China would implement policies that truly reward hard work and innovation, rather than continuing its policies that distort the vital high-tech sector. "Unfortunately, China has chosen to respond thus far with threats to impose unjustified tariffs on billions of dollars in U.S. exports, including our agricultural products. Such measures would undoubtedly cause further harm to American workers, farmers, and businesses. Under these circumstances, the President is right to ask for additional appropriate action to obtain the elimination of the unfair acts, policies, and practices identified in USTR's report." Any additional tariffs proposed will be subject to a similar public comment process as the proposed tariffs announced on April 3, 2018. No tariffs will go into effect until the respective process is complete.

—CNBC's Evelyn Cheng contributed to this report.