A SpaceX Crew Dragon capsule carrying two NASA astronauts docked Sunday with the International Space Station, the first time a crewed US spacecraft has performed the feat in nearly a decade.

"Soft capture," the moment when the spacecraft makes first contact and starts latching with the target vehicle, occurred at 10:16 am Eastern Time (1416 GMT).

It was followed a few minutes later by "hard capture" when an airtight seal was completed.

On board are astronauts Bob Behnkhen and Doug Hurley, both veterans of the Space Shuttle program that was shuttered in 2011.

"We copy docking is complete," said a member of the crew.

"It's been a real honor to be a small part of this nine-year endeavor since the last time a United States spaceship has docked with the International Space Station."

Next, the vestibule between the Dragon and the International Space Station will be pressurized and the hatch will then be opened, in about an hour.

The launch on Saturday by SpaceX, the private rocket company of billionaire entrepreneur Elon Musk, represented another milestone for the reusable rockets it pioneered to make spaceflight less costly and more frequent.

It also marked the first time that commercially developed space vehicles - owned and operated by a private entity rather than NASA - have carried Americans into orbit.

A SpaceX Falcon 9 rocket lifted off from the Kennedy Space Center at 3:22 p.m. EDT (1922 GMT) for the journey to the International Space Station. Just before liftoff, Hurley said, "SpaceX, we're going for launch. Let's light this candle," paraphrasing the famous comment uttered on the launch pad in 1961 by Alan Shepard, the first American flown into space.