The private US company SpaceX Monday postponed the launch of a rocket carrying a telecoms satellite.

The launch with a Falcon 9 rocket had been scheduled for Monday from Florida. But the company said it has delayed it until Thursday because of unexpected readings in the fuel system.

It was to be the first launch with an improved version of the Falcon 9 after a test flight in California.

SpaceX is eager to get into the commercial satellite launch business, estimated to be worth 190 billion dollars a year, with competitive prices.

This time it was to launch a satellite for the Luxembourg company SES, the second largest in the world in that sector.

Until now SES has used European Ariane rockets or the Russian Proton. These are much more expensive than the $55 million charged by SpaceX, said Martin Halliwell, technology director at SES.

The SES satellite is to provide television, cable TV and other services to countries including China, Vietnam and India.

The Falcon 9 has already succeeded in sending its Dragon capsules to the International Space Station under a contract with NASA.

The capsule takes cargo into space and brings back material from scientific experiments.