China has refused a US request for a phone call between its defense secretary, Lloyd Austin, and his Chinese counterpart, Wei Fenghe, on the day a US fighter jet shot down a Chinese balloon, a US official said Tuesday.

"On Saturday, February 4, immediately after action was taken to shoot down the PRC balloon, the Department of Defense submitted a request for a secure call between Secretary of Defense Austin and PRC Minister of National Defense Wei Fenghe," said Department of Defense spokesman Pat Ryder - in a statement.

"Communications between our two militaries are especially important at times like this. Unfortunately, our request has been rejected by the People's Republic of China. Our commitment to open lines of communication continues," he added.

China says that the balloon that was dropped over American airspace was intended for meteorological purposes and had no military purpose, but Washington described it as an advanced espionage mechanism operating from high altitudes.

After slowly crossing the center of the United States over several top-secret military sites - according to reports - the balloon headed towards the American east coast.

The balloon was shot down by a US fighter plane on Saturday off the coast over the Atlantic Ocean, and the Navy and Coast Guard are currently trying to recover the wreckage for analysis.

On Monday, the Chinese government said the United States had "severely affected and damaged" relations between the two countries with its decision to shoot down the balloon.