The last of the debris fro the Chinese balloon, which was downed by a Sidewinder missile, is heading to an FBI laboratory in Virginia for analysis, the U.S. military's Northern Command said in a statement.

Reuters was first to report the conclusion of the recovery efforts, which were halted on Thursday.

"It's a significant amount (of recovered material), including the payload structure as well as some of the electronics and the optics, and all that's now at the FBI laboratory in Quantico," said National Security Council spokesperson John Kirby.

Kirby said the United States had already learned a lot about the balloon by observing it as it flew over the United States.

"We're going to learn even more, we believe, by getting a look at the guts inside it and seeing how it worked and what it was capable of," he told a White House news briefing.

The U.S. military said Navy and Coast Guard vessels that had been scouring the sea for nearly two weeks have departed the area.

"Air and maritime safety perimeters have been lifted," Northern Command said in a statement.

The U.S. military has said it believes it has collected all of the Chinese balloon's priority sensors and electronics as well as large sections of its structure, elements that could help counterintelligence officials determine how Beijing may have been collecting and transmitting surveillance information.

The Chinese balloon, which Beijing denies was a government spy vessel, spent a week flying over the United States and Canada before being shot down off the Atlantic Coast on orders from President Joe Biden.

The episode caused an uproar in Washington and led the U.S. military to search the skies for other objects that were not being captured on radar. The military's Northern Command carried out an unprecedented three shootdowns of unidentified "objects" between last Friday and Sunday.

But Biden's administration sought on Friday to temper expectations about recovery efforts for those three objects, which fell over challenging terrain and, in one case, the very deep waters of Lake Huron.

"We all have to accept the possibility that we may not be able to recover it," Kirby said, noting it would be difficult to identify those objects without finding debris.

The Chinese balloon incident also prompted U.S. Secretary of State Antony Blinken to postpone a planned visit earlier this month to Beijing and has further strained already frayed ties between Washington and Beijing.

That Blinken trip would have been the first by a U.S. secretary of state to China in five years and was seen by both sides as an opportunity to stabilize increasingly fraught ties.

U.S. officials have since been looking at the possibility of a meeting between Blinken and China's top diplomat Wang Yi on the sidelines of the Munich Security Conference that began on Friday.

U.S. Vice President Kamala Harris, who is also in Munich for the conference, has defended the administration's handling of the balloon incident and the shooting down of the three other objects.

The Chinese balloon "needed to be shot down because we were confident that it was used by China to spy on American people," Harris told MSNBC.

"We will maintain the perspective that we have in terms of what should be the relationship between China and the United States," she said. "That is not going to change, but surely and certainly that balloon was not helpful."