MOSCOW, December 23. /TASS/. The launch of a Proton-M carrier rocket with an EchoStar 21 satellite from the Baikonur space center in Kazakhstan has been delayed over the need to hold additional checks of the rocket’s systems and acceleration unit, Russia’s Khrunichev Space Center reported on Friday.

The Khrunichev Space Center is the producer of Proton carrier rockets.

The launch was scheduled for December 28, about which the Khrunichev Space Center reported on Monday.

"The state commission has taken a decision to postpone the date of the launch of the Proton-M space rocket with the EchoStar 21 satellite to hold additional checks of the carrier rocket’s systems and acceleration unit. The launch date will be announced additionally," the statement said.

The launch was initially scheduled for the first quarter of 2016 but was postponed several times.

The EchoStar 21, earlier called EchoStar T2 and TerreStar 2, was produced by the company Space Systems/Loral and is designated to provide services on the territory of Europe. The satellite is to become the sixth in the EchoStar orbital grouping after it is launched by the Proton rocket.

The previous launch of the Proton carrier rocket took place on June 9: the carrier rocket orbited an Intelsat 31 satellite.