President Joe Biden said he does not apologize for shooting down a Chinese spy ball off the coast of the United States.
He said the balloon was used for surveillance, but the three other objects shot down over North America were unlikely to be foreign spy ships.
According to him, now the USA will improve the detection of similar aerial objects.
Mr. Biden also said he would soon speak with Chinese President Xi Jinping about the incident this month.
“Hopefully we’ll get to the bottom of it, but I don’t apologize for taking down that balloon,” Mr. Biden said at the White House on Thursday.
China has denied that the balloon was being used for surveillance, saying instead that it went off course while gathering weather data.
But Mr Biden echoed US officials’ view that the balloon, which crossed the country at about 40,000 feet (12,000 m) before being shot down by a US fighter jet over the Atlantic, was actually being used for espionage.
According to him, the USA continues negotiations with China on this issue. “We are not looking for a new Cold War,” Mr. Biden said.
Pressure is mounting on Joe Biden to speak directly to the public about the alleged Chinese surveillance balloon, as well as three unidentified objects that US fighter jets have attempted to destroy over the past week.
On Thursday afternoon, he did, but his brief appearance did little to silence critics or those asking for more information and clarification.
He did not shed light on the nature of these objects and did not provide additional information about the first Chinese balloon. He did not discuss when the Chinese balloon was first detected, its intended purpose or recent reports that it was aimed at the US island of Guam but then changed course. He also did not say why new targets were not targeted after last week’s series of incidents.
Referring to three other objects later shot down over Alaska, northwestern Canada and Lake Huron on the US-Canada border, Mr. Biden said the intelligence community believed they were “most likely balloons associated with private companies, recreational or research institutions”.
The president said the advanced radar introduced in response to the Chinese balloon could explain the discovery of the three objects.
“That is why I have instructed my team to come back to me with clearer rules on how we will deal with these unidentified objects going forward, distinguishing between those that are likely to pose a safety and security threat that requires action and those that do not need “
Mr. Biden’s comments came after the White House felt the need to refute suggestions that the three objects were of extraterrestrial origin.
Officials said the slow-moving unidentified objects posed “no direct threat to people on the ground” and were destroyed “to protect our safety, interests and flight safety.”
As for whether he would take similar action again, Mr. Biden said: “Make no mistake, if any facility poses a threat to the safety and security of the American people, I will destroy it.”
He declined to say when he planned to speak with Chinese President Xi when asked during an interview with NBC News.
“I think the last thing Xi wants is to fundamentally break the relationship with the United States and with me,” Biden told the broadcaster.
China repeated its explanation for the balloon shot down on February 4, and a spokesman told reporters that the US should try to avoid “misunderstandings and misjudgments”.
Amid heightened tensions in the skies over the US, military officials said Thursday that US warplanes intercepted Russian jets flying near Alaska for the second time this week.
The North American Aerospace Defense Command (Norad), which is jointly run by the US and Canada, said in a statement that it was a “routine” contact with the Russians.