"My sense is that they do not react well to bludgeoning," Kerry said of the Chinese, in an interview on CNBC's "Closing Bell." "It will probably take them a lot longer, and they are also in a bigger driver's seat than Canada or Mexico because of the size of their economy."
The U.S. and China, the world's two largest economies, have been locked in a trade war for months, and just last week the Trump administration implemented a new round of 10 percent duties on $200 billion worth of Chinese goods. Those tariffs are set to rise to 25 percent at the start of 2019.
Kerry's comments came just hours after the U.S. struck a deal with its North American neighbors late Sunday ahead of a self-imposed Monday deadline. The new deal retooled some provisions of the North American Free Trade Agreement, particularly with regard to automakers and dairy farmers, and goes by a new name: the United States-Mexico-Canada Agreement, or USMCA.
At an event unveiling the trade agreement on Monday, Trump raised the prospect of a new China deal, but said that it was "too soon" to begin bilateral talks.
"China wants to talk, very badly, and I said, 'Frankly, it's too early to talk.' Can't talk now, because they're not ready," Trump said. "If, politically, people force it too quickly, you're not going to make the right deal for our workers and for our country."
Kerry and Trump went after each other last month. After Kerry told the BBC that Trump was "the worst president in American history," Trump accused Kerry of breaking the law by meeting with Iranian officials.
"John Kerry had illegal meetings with the very hostile Iranian Regime, which can only serve to undercut our great work to the detriment of the American people," Trump wrote on Twitter.
Kerry said Monday that he "never undermined their policy one iota," and suggested that Trump's attacks may have been meant as a distraction.
"Since the administration has pulled out [of the Iran nuclear deal], I have made no effort to talk to anybody from Iran about this agreement," the former secretary of State said.
Kerry also suggested that the "hysteria was articulated on the very day that Manafort cut a deal with Mueller," though the president's tweet was sent the day before Paul Manafort, the president's former campaign boss, cut a deal with the special counsel.
The White House did not immediately respond to a request for comment.