She suggested high winds at Joint Base Andrews near Washington may have been a factor.
“It’s very windy,” Jean-Pierre said when asked about his stumbling. “He is doing 100% fine.”
NewsNation Washington affiliate station’s forecast shows “blustery winds, blowing steady at around 20-30 mph with gusts up to 35-40 mph” for Friday.
Jean-Pierre said she nearly fell coming up the steps as well because of the wind. She did not say whether Biden had been checked by a traveling physician after.
Boarding a flight to Atlanta, where he was to speak to the Asian-American community about a shooting at three massage parlors there earlier this week that killed eight, Biden stumbled slightly about halfway up the 25 or so stairs, recovered, then stumbled again and briefly went down on one knee, according to video footage.
The president appeared to rub his left knee before getting back up, then completed the stairs at a slower pace. He stopped at the top of the stairs, turned around and offered a crisp salute.
In late November, Biden suffered a hairline fracture in his right foot while playing with one of his dogs.
At 78, Biden was the oldest person ever to assume the presidency when he entered the White House on Jan. 20. The oldest president at the end of his tenure was Ronald Reagan, leaving the White House at age 77.
Reuters contributed to this report; all reporting by Trevor Hunnicutt, Steve Holland and Heather Timmons