The collision of elements during the separation of the carrier rocket’s first and second stages is the primary cause of the Soyuz-FG booster’s abortive launch, Roscosmos Executive Director for Manned Flights Sergei Krikalyov said on Friday. This reported by TASS.

"There are no final versions but the primary cause is understandable and is related to the collision of a side element making part of the first stage. A collision occurred during the separation of the first and second stages," the Roscosmos official said.

"A deviation from the standard trajectory occurred and apparently the lower part of the second stage disintegrated. The rocket stopped its normal flight and after that the automatic system did its work," Krikalyov said.

The dates of launches of a cargo spacecraft Progress MS to the International Space Station may be revised following the failure of the Soyuz-FG rocket. "Possibly, we may revise the date of launching the next cargo spacecraft. Possibly, we will speed up the launch of the next Soyuz. Different versions of the program are being considered," Krikalyov said.