"Sea Launch has put on hold the countdown for the launch of the DirecTV satellite, as of late Sunday afternoon, to allow the team to study an issue. We will update our launch information as it becomes available," the company said on its website.
The launch from the Odyssey platform set to carry the Boeing-made TV satellite weighing around six metric tons was scheduled for 6:49 p.m. EDT (22:49 GMT).
The satellite will broadcast high-definition TV to subscribers in the U.S.
The Sea Launch consortium, established in 1995, is owned by Boeing, Norway's Kvaerner ASA, Ukraine's Yuzhnoye design bureau and the Yuzhmash production association, as well Russia's RSC-Energia, and is the only company which launches its vehicles from the equator, allowing rockets to carry heavier payloads than from other latitudes.
The launch will be the consortium's fourth for DirecTV.
Sea Launch has performed 25 commercial launches for companies including EchoStar, DirecTV, XM Satellite Radio, and PanAmSat.