US Navy divers are working to recover the wreckage of the Chinese surveillance balloon that was shot down off the coast of South Carolina.
America's former top military officer said he expected it would happen relatively quickly so that experts could begin analysing its equipment.
Fighter jets brought the craft down over US territorial waters on Saturday and debris is spread over a wide area.
The US believes the balloon was monitoring sensitive military sites.
Its discovery set off a diplomatic crisis, with US Secretary of State Antony Blinken immediately calling off this weekend's trip to China over the "irresponsible act".
The Chinese authorities denied it was used for spying and insisted it was a weather ship blown astray.
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Admiral Mike Mullen, former chair of the US Joint Chiefs of Staff, said on Sunday he thought the Chinese military might have launched the balloon intentionally to disrupt Mr Blinken's trip to China. His visit would have been the first such high level US-China meeting there in years.
Adm Mullen rejected China's suggestion it might have blown off course, saying it was manoeuvrable because "it has propellers on it".
"This was not an accident. This was deliberate. It was intelligence," he added.
Republican politicians have accused US President Joe Biden of a dereliction of duty for allowing the balloon to traverse the country unhindered.
Marco Rubio, vice-chair of the Senate intelligence committee, told CNN it was a "brazen effort" by China to embarrass the president ahead of his State of the Union address on Tuesday.
The Republican chairman of the House intelligence committee, Mike Turner, said the Biden administration had not recognised the "urgency" of the situation, adding: "Clearly this was an attempt by China to gather information, to defeat our command and control of our sensitive missile defence and nuclear weapon sites."
Top Senate Democrat Chuck Schumer confirmed on Sunday that senators would be briefed this month about the balloon and its surveillance capabilities.
The high-altitude balloon - thought to be the size of three buses - was shot out of the sky by a Sidewinder air-to-air missile fired from an F-22 jet fighter. It came down about six nautical miles off the US coast at 14:39 EST (19:39 GMT) on Saturday.
US TV networks broadcast the moment the missile struck, with the giant white object falling to the sea after a small explosion.
The debris landed in 47ft (14m) of water - shallower than they had expected - and is spread over seven miles (11km).
Explaining the decision to shoot the balloon down, a US defence official said in a statement, that "while we took all necessary steps to protect against the PRC [China] surveillance balloon's collection of sensitive information, the surveillance balloon's overflight of US territory was of intelligence value to us."