Beijing has blasted US President Joe Biden for his "extremely irresponsible" comments about Chinese President Xi Jinping that he is struggling with "enormous problems" back home.
Last week, the US military downed a high-altitude Chinese balloon off the coast of South Carolina after the craft crossed directly over at least one sensitive US military site. Washington claims the device was intended for espionage.
The US also alleged that the balloon, conducting a high-tech spying operation, was part of a spy "fleet" spanning five continents, claiming that such devices had been spotted around the world for several years and urged allies to boost vigilance.
China has angrily rejected the allegations, arguing it was only a weather observation craft that blew off course.
"This irresponsible and seriously mistaken approach by the US did not create a proper atmosphere for dialog and exchanges between the two militaries," China's defense ministry said in a statement on Thursday.
It also confirmed that Beijing refused an offer of a call with the US defense chief because of Washington’s “irresponsible” decision to shoot down the balloon.
“This irresponsible and seriously mistaken approach by the US did not create a proper atmosphere for dialogue and exchanges between the two militaries,“ it said.
The Chinese Defense Ministry also said Washington "insisted on using force to attack the airship, which seriously violated international practice and sets a bad precedent."
“China reserves the right to use necessary means to deal with similar situations,” it said.
A day earlier, Biden, in an interview with PBS NewsHour, defended the decision to shoot down the balloon in US airspace. He said the US is not looking for conflict with China.
The US president also said Xi had "enormous problems", including "an economy that is not functioning very well."
"Can you think of any other world leader who'd trade places with Xi Jinping? I can't think of one," Biden said.
Beijing on Thursday firmly responded to Biden's remarks, with Chinese Foreign Ministry spokeswoman Mao Ning saying the Chinese government was "strongly dissatisfied."
"This type of rhetoric from the US is extremely irresponsible and runs counter to basic diplomatic etiquette," Mao said, adding that Beijing "firmly opposed this."
Beijing reiterated that the balloon was for civilian purposes. It said claims that it was part of a fleet were just part of an "information war" against China.
"The US disregard for China's repeated explanations and communications, excessive reaction, and misuse of force are irresponsible. The international community can see very clearly what the world's biggest country of espionage, monitoring and surveillance is," Mao said.
Following the new rhetorical skirmish, US-China relations once again nosedived, with US Secretary of State Antony Blinken last week calling off a visit to Beijing over the balloon incident.
Separately on Wednesday, NATO Secretary General Jens Stoltenberg claimed that the Chinese balloon presented security challenges for NATO’s 30-member alliance as well as other countries around the globe, saying the incident showed the need for countries across the alliance to protect themselves.
"The Chinese balloon over the United States confirms a pattern of Chinese behavior where we see that China over the last years has invested heavily in new military capabilities," he said during a visit to Washington.
"We've also seen increased Chinese intelligence activities in Europe. They use satellites, they use cyber and, as we've seen over the United States, also balloons," Stoltenberg said.