Republicans lashed into Joe Biden on Sunday over his handling of the suspected Chinese spy balloon, while Democrats defended the president's decision to shoot it down after it floated across the United States for days, further straining taut relations with Beijing.

With efforts to retrieve balloon debris continuing off the South Carolina coast one day after a US fighter jet downed the large airship, the incident sparked fiery debate over Biden's dealing with the matter and how US-Chinese ties might suffer.

"As usual when it comes to national defence and foreign policy, the Biden administration reacted at first too indecisively and then too late," Senate Republican leader Mitch McConnell said on Twitter.

"We should not have let the People's Republic of China make a mockery of our airspace."

Marco Rubio, vice chair of the Senate intelligence committee, said on CNN that the president's delay in alerting the public to the balloon's presence amounted to "dereliction of duty."

And Representative Mike Turner, who chairs the US House intelligence committee, used a football analogy in blasting Biden.

"Clearly the president taking it down over the Atlantic is... sort of like tackling the quarterback after the game is over," he said on NBC.

"The satellite had completed its mission. It should never have been allowed to enter the United States."

Democrats quickly pushed back, calling the Republican criticisms "premature and political."

Chuck Schumer, the Senate Democratic leader, insisted the administration had "made the right call."

"We sent a clear message to China that this is unacceptable," he said in a statement. "We protected civilians. We gained more intel while protecting our own sensitive information."

The downing of the balloon by an F-22 fighter jet "wasn't just the safest option, but it was the one that maximized our intel gain," Schumer said -- because any instrumentation on the huge airship was more likely to survive a water landing.

He said the full Senate would receive a classified briefing on February 15.