Christina Koch and Anne McClain were set to be the first female crew to conduct a spacewalk at the International Space Station.
NASA has cancelled plans for the first all-female spacewalk aboard the International Space Station because of a shortage of appropriate spacesuits.
Christina Koch and Anne McClain were due to embark on the historic assignment on Friday.
Ms McClain had performed the first spacewalk of her career with fellow astronaut Nick Hague on 22 March.
But the space agency says the all-female pairing now has to be delayed because only one medium-sized spacesuit is available.
In a statement, NASA added: "Koch had been scheduled to conduct this spacewalk with astronaut McClain, in what would have been the first all-female spacewalk.
"However, after consulting with McClain and Hague following the first spacewalk, mission managers decided to adjust the assignments, due in part to spacesuit availability on the station."
During the assignment, NASA says Ms McClain learned "that a medium-size hard upper torso - essentially the shirt of the spacesuit - fits her best".
Only one of these is available aboard the ISS for Friday's mission, prompting NASA to decide that it should be worn by Ms Koch so she can embark on the first spacewalk of her career.
"McClain now is tentatively scheduled to perform her next spacewalk - the third in this series - on Monday 8 April with Canadian Space Agency astronaut David Saint-Jacques," NASA added.
Friday's spacewalk will see the astronauts continue work to install "powerful lithium-ion batteries for one pair of the station's solar arrays".
Ms McClain was the 13th woman to perform a spacewalk, and Ms Koch is going to become the 14th.
They were both part of NASA's 2013 Astronaut Class, made up of four men and four women.
NASA is about halfway through replacing 48 batteries with ones that are expected to last the remainder of the station's life.
The space station uses solar panels to generate power, however the batteries are used when it is in the dark and not getting power from the sun.
PUKmedia / SkyNews