MIAMI - Two US astronauts began the 200th spacewalk at the International Space Station on Friday, following a brief delay after NASA discovered a water leak in equipment that helps power their spacesuits.

The official start time, 9:08 am, was about two hours after it was supposed to begin, according to NASA.

The glitch affected equipment known as the servicing and cooling umbilical, which supplies power and oxygen to the spacesuits worn by veteran US astronaut Peggy Whitson, 57, and her rookie counterpart, Jack Fischer, 43.