Defence Minister Wei Fenghe hit back in a fiery address at the same event, saying Beijing had “no choice” but to fight if attempts are made to separate Taiwan from China.
“We will fight at all cost, and we will fight to the very end,” he said.
“No one should ever underestimate the resolve and ability of the Chinese armed forces to safeguard its territorial integrity.”
“Those who pursue Taiwanese independence in an attempt to split China will definitely come to no good end,” he added.
Wei urged Washington to “stop smearing and containing China... stop interfering in China’s internal affairs and stop harming China’s interests,” he said.
But he also struck a more conciliatory tone at points, calling for a “stable” China-US relationship, which he said was “vital for global peace”.
During his address, Austin also said he wants “lines of communication” with Chinese officials to remain open.
The pair held their first face-to-face talks on the sidelines of the summit in Singapore on Friday, during which they clashed over Taiwan.
Tensions over Taiwan have escalated in particular due to increasing Chinese military aircraft incursions into the island’s air defence identification zone (ADIZ).
President Joe Biden, during a visit to Japan last month, appeared to break decades of US policy when, in response to a question, he said Washington would defend Taiwan militarily if it was attacked by China.
The White House has since insisted its policy of “strategic ambiguity” over whether or not it would intervene had not changed.
The dispute is just the latest between Washington and Beijing.
Another major flashpoint has been the South China Sea.
China claims almost all of the resource-rich sea, through which trillions of dollars in shipping trade passes annually, with competing claims from Brunei, Malaysia, the Philippines, Taiwan and Vietnam.
The United States and China have also been at loggerheads over Russia’s invasion of Ukraine, with Washington accusing Beijing of providing tacit support for Moscow.