SpaceX said Tuesday it has postponed its February test flight of the Dragon capsule to the International Space Station, the first-ever bid by a private company to dock at the orbiting lab.

The delay is due to technical reasons and a new launch date for the unmanned mission has not been set.

"In preparation for the upcoming launch, SpaceX continues to conduct extensive testing and analysis," spokeswoman Kirstin Grantham said in an email to AFP.

"We believe that there are a few areas that will benefit from additional work and will optimize the safety and success of this mission. We are now working with NASA to establish a new target launch date."

SpaceX -- owned by Elon Musk, an Internet entrepreneur and founder of PayPal -- in December 2010 became the first commercial outfit to send its Dragon spacecraft into orbit and back.

The next steps -- a fly-by and berthing mission at the ISS -- were initially scheduled for February 7, but NASA said in December that date could change because "a significant amount of critical work" remained before launch.

SpaceX and several other companies are competing to be the first to operate a private capsule that could tote astronauts and cargo to the ISS, after NASA retired its space shuttle program last year.

The main goals of SpaceX's next flight include a fly-by of the ISS at a distance of two miles, and a berthing operation in which Dragon will approach the ISS and the crew aboard the orbiting outpost will use the ISS robotic arm to help it latch on.

After the test mission, the Dragon aims to detach from the station for its return to Earth and eventually splash down in the Pacific off the coast of California.