The two newly arrived giant pandas at the National Zoo in Washington DC will have plenty of time to overcome any jet lag, as they won't make their public debut until the new year.

Bao Li and Qing Bao, both 3 years old, were flown Monday from the Dujiangyan base of the China Conservation and Research Center for the Giant Panda and were taken to Chengdu Shuangliu International Airport.

They made a refueling stop in Alaska — and some 19 hours later — landed at Dulles International Airport in suburban Virginia. They then were loaded into special FedEx trucks and got to the zoo on Tuesday before noon.

The pandas' FedEx plane — a Boeing 777F cargo jet dubbed the "Panda Express" — and the trucks that transported them were both adorned with panda images.

"Two 'treasures' arrived at the Zoo today! Join us in welcoming giant pandas Bao Li and Qing Bao, who entered Zoo grounds shortly after 11:30 am today and are settling into their new homes at the David M. Rubenstein Family Giant Panda Habitat," the zoo posted Tuesday on X.

The social media post included a video that showed the pandas' dramatic arrival, variously surveying their new surroundings, chomping on bamboo, testing the waters in a stone wading pool, and letting out an understandable yawn.

"Our team has worked tirelessly to prepare for the pandas' arrival, and we're thrilled to welcome Bao Li and Qing Bao to Washington DC, the only place you can see giant pandas for free in the nation," said Brandie Smith, the National Zoo director who traveled to China to take part in farewell ceremonies for the bears there. "As a result of our collective efforts, today we joyfully celebrate a new chapter of our 52-year-long giant panda breeding and conservation program.

"I am appreciative of our Chinese colleagues for our collaborative conservation and research efforts, to FedEx for providing them with safe transportation and to our donors and members whose philanthropic contributions makes our giant panda conservation program possible," said Smith.

The zoo, which is part of the Smithsonian Institution, was closed Tuesday to focus on the arrival of the bears, who will be quarantined from the public for at least 30 days.

A zoo statement scheduled their public debut and the reopening of the renovated panda house for Jan 24, 2025.

During a news conference on Tuesday, Chinese Foreign Ministry spokeswoman Mao Ning said that experts will be sent to the US to conduct on-site inspections and evaluations and offer guidance.

"In accordance with the requirements and technical standards of international cooperation for giant panda conservation, China and the US will spare no effort to ensure the health and safety of giant pandas residing in the US," she said.

US Ambassador to China Nicholas Burns posted on X: "The pandas — Bao Li and Qing Bao — are back in Washington DC. Congratulations to the @National Zoo. Pandas have been a fixture in our nation's capital since President Nixon went to China 52 years ago."

Bao Li, a male whose name means "treasure" and "energy" in Chinese, was born in August 2021. He shares a special bond with the zoo, as he is the son of Bao Bao and the grandson of Tian Tian and Mei Xiang — all former residents of the National Zoo.

Qing Bao, a female, whose name means "green" and "treasure" in Chinese, was born in September 2021.

In Washington, traffic stopped Tuesday along Connecticut Avenue as the panda motorcade arrived at the zoo, The New York Times reported.

"You know, when Mei Xiang, Tian Tian and Xiao Qi Ji left, I felt like I was losing my best friends in a way," a teary Kirsten Svane, who was sporting panda ears, told the Times.

"You just really get to know their personality, what they like, what they don't like, their habits, like everything," she said. "I'm excited to be able to, you know, form that relationship again."

In an article published on the Reader's Digest website on Tuesday, veteran travel writer Anne Fritz recounted her memories of seeing pandas in Washington.

"When I was a kid growing up in the Washington DC, area, it was always a big treat to visit the National Zoo pandas, Ling-Ling and Hsing-Hsing, on school field trips or with my parents," Fritz wrote.

She said that in 2018, "it was my turn to introduce my two kids to Mei Xiang and Tian Tian, the giant pandas that China loaned to the United States shortly after the passing of the original pair".

"We all watched as the black-and-white cuddly bears, along with their cub, Bei-Bei, munched on bamboo — with the same delight I remember experiencing as a child."

The new pandas arrived in Washington as part of a new 10-year agreement with China. The previous deal expired last year, leading to some concern among American panda-lovers over whether new bears would arrive.

It is the second time this year that China has sent giant pandas to the United States. Yun Chuan and Xin Bao landed in California on June 27, and made their public debut at the San Diego Zoo on Aug 9.

Yan Dongjie in Beijing, Zhao Huanxin in New York, and agencies contributed to this story.