US House unanimously condemns Chinese balloon

US lawmakers unanimously denounced China's use of a suspected spy balloon that flew over North America last week.

The vote allowed lawmakers to agree on a bipartisan stance on Beijing, after several balloon-related political skirmishes.

The balloon's days-long flyover from Alaska to South Carolina captured the attention of regular Americans and officials alike, before the US military shot it down off the east coast Saturday.

The House of Representatives passed a resolution "condemning the Chinese Communist Party's use of a high-altitude surveillance balloon over United States territory as a brazen violation of United States sovereignty."

Republicans heavily criticised President Joe Biden's response to the incursion, accusing his administration of being weak in the face of Chinese aggression.

According to Biden, military officials warned that falling debris could have posed a risk to the American population on the ground if the balloon and its high-tech payload — whose remnants ultimately ended up in the Atlantic Ocean — had been shot down earlier, while it was over land.

For congressman Michael McCaul, the resolution's sponsor, the balloon affair offered a silver lining: "The good news is it galvanized the American people's opposition to Chairman Xi (Jinping)'s communist regime," he said.

A Pentagon official told a separate Senate hearing Thursday that the United States is still trying to figure out what exactly the balloon, which it says was deployed for espionage purposes, was looking for.

"We have some very good guesses about that," assistant defence secretary Jedidiah Royal said.

"We are learning more as we exploit the contents" of the balloon, he added.

Beijing has insisted the balloon was a "civilian airship used for research, mainly meteorological purposes."