Two U.S. astronauts who arrived at the International Space Station aboard Boeing's Starliner will have to return home with SpaceX, NASA said Saturday.

"NASA has decided that Butch and Suni will return with Crew-9 next February, and that Starliner will return uncrewed," NASA administrator Bill Nelson told reporters.

The return of Barry "Butch" Wilmore and Sunita "Suni" Williams has been delayed by thruster malfunctions of the Boeing spacecraft.