U.S. military fighter aircraft shot down a suspected Chinese spy balloon as it floated off the coast of South Carolina on Saturday, drawing to a close a dramatic saga that shone a spotlight on worsening Sino-U.S. relations.

"We successfully took it down, and I want to compliment our aviators who did it," President Joe Biden said.

Biden said he had issued an order on Wednesday to take down the balloon, but the Pentagon had recommended waiting until it could be done over open water to safeguard civilians from debris crashing down to Earth from thousands of feet (meters) above commercial air traffic.

Multiple fighter and refueling aircraft were involved in the mission, but only one -- an F-22 fighter jet from Langley Air Force Base in Virginia -- took the shot at 2:39 p.m. (1939 GMT), using a single AIM-9X supersonic, heat-seeking, air-to-air missile, a senior U.S. military official said.

The balloon was shot down about six nautical miles off the U.S. coast, over relatively shallow water, potentially aiding efforts to recover key elements of the Chinese surveillance equipment among the debris in the coming days, officials said.

The shootdown came shortly after the U.S. government ordered a halt to flights in and out of three South Carolina airports -- Wilmington, Myrtle Beach and Charleston -- due to what it said at the time was an undisclosed "national security effort." The flights resumed on Saturday afternoon.

The balloon first entered U.S. airspace on Jan. 28 before moving into Canadian airspace on Monday Jan 30. It then re-entered U.S. airspace on Jan. 31, a U.S. defense official said. Once it crossed over U.S. land, it did not return to the open waters, making a shootdown difficult.

U.S. officials did not publicly disclose the balloon's presence over the United States until Thursday.

Washington has called it a "clear violation" of U.S. sovereignty and notified Beijing about the shootdown on Saturday, a U.S. official said.

"Our assessment -- and we're going to learn more as we pick up the debris -- was that it was not likely to provide significant additive value over and above other (Chinese) intel capability, such as satellites in low-Earth orbit," the senior U.S. defense official said. Defense Secretary Lloyd Austin first announced the shootdown, saying the balloon was being used by China "in an attempt to surveil strategic sites in the continental United States."

A Reuters photographer who witnessed the shootdown said a stream came from a jet and hit the balloon, but there was no explosion. It then began to fall, the photographer said.

The U.S. military did not immediately recover the payload from the Chinese surveillance balloon, U.S. officials said.

The FAA had issued a temporary flight restriction to clear airspace around the South Carolina coast. The notice blocked flights to more than 100 square miles (260 square kilometers) -- mostly over the Atlantic Ocean, according to a document posted by the FAA. The notice warned the military could use deadly force if airplanes violate the restrictions and do not comply with orders to leave.

The Reuters photographer in the Myrtle Beach area could see the suspected spy balloon overhead, with two U.S. military jets flying alongside it.

China expressed regret that an "airship" used for civilian meteorological and other scientific purposes had strayed into U.S. airspace.

China's foreign ministry said on Saturday that the flight of the "airship" over the United States was a force majeure accident, and accused U.S. politicians and media of taking advantage of the situation to discredit Beijing.

But the Pentagon assesses that the balloon was just the latest in a string of Chinese spy balloon activity spanning the globe. On Friday, it said another Chinese balloon was currently flying over Latin America.

"Over the past several years, Chinese balloons have previously been spotted over countries across five continents, including in East Asia, South Asia and Europe," the senior defense official said. The suspected Chinese spy balloon prompted U.S. Secretary of State Antony Blinken to postpone a visit to China this week that had been expected to start on Friday.

The postponement of Blinken's trip, which had been agreed to in November by Biden and Chinese President Xi Jinping, is a blow to those who saw it as an overdue opportunity to stabilize an increasingly fractious relationship between the two countries.

China is keen for a stable U.S. relationship so it can focus on its economy, battered by the now-abandoned zero-COVID policy and neglected by foreign investors alarmed by what they see as a return of state intervention in the market.