Prime Minister Vladimir Putin on Friday fired the Russian space agency chief after a series of high-profile setbacks cast a shadow on the 50th anniversary year of Yuri Gagarin's first space flight.

Anatoly Perminov will be replaced as head of Roskosmos by First Deputy Defence Minister Vladimir Popovkin, the government said in a statement, quoting an order signed by Putin.

The order said Perminov had reached the maximum age for state employees but there have been clear indications for some time of growing frustration in the government with Roskosmos' performance.

Russia in December suffered one its most embarrassing space failures in recent times when three navigation satellites for the new Russian Glonass system crashed into the ocean off Hawaii instead of reaching orbit.

Officials later admitted that a simple fuel miscalculation was to blame. In February, Russia then put its new Geo-IK-2 military satellite into the wrong orbit, rendering it useless for defence purposes.

Reports have said that the last straw was when the latest manned launch for the International Space Station was delayed due to a technical problem just two weeks ahead of the Gagarin anniversary.

Russia on April 12 marked 50 years since Gargarin's historic first space flight with huge fanfare and President Dmitry Medvedev made clear in a Kremlin address that space exploration remained a priority for the country.

"It's quite clear what the cause is," leading defence analyst Alexander Goltz told Moscow Echo radio station, commenting on Perminov's departure.

"The most recent failures of Roskosmos like the failed Glonass launch and much else shows the clear worsening of technological discipline in its units."

Perminov has served as Roskosmos chief since March 2004.

Popovkin served at the Baikonur space station in Kazakhstan after finishing military academy and headed Russian missile and space defence forces between 2004 and 2008.

Goltz said that at the defence ministry Popovkin had shown himself to be a capable organiser with a good vision of the future.

"The question is to what extent there has been a degradation in Roskosmos' technological units and whether an organiser like Popovkin can change the situation," he said.

Deputy Prime Minister Sergei Ivanov in February issued a scathing assessment of Roskosmos' performance, saying that the Glonass mishap was characteristic of its problems.

"I won't go into details, this was a mistake, but a childish one and a mistake that had serious consequences," he said, describing any repeat satellite failure as "unacceptable".

The failed launch of the Glonass satellites alone had cost Russia 2.5 billion rubles ($86 million, 63 million euros).

The Russian space programme suffered from a sharp drop in funding after the fall of the Soviet Union, and Roskosmos has sent several paying space tourists to the International Space Station (ISS) to help make ends meet.

Yet the onus on Russia is set to grow when NASA takes the US shuttle out of service this year, leaving the Russian Soyuz rockets and spacecraft as the sole delivery systems for taking humans to the ISS.

According to Ivanov, Russia last year remained the world leader in the number of space launches, with 31, while the United States managed 16.

A crucial moment will come later this year with the launch of the much-delayed Fobos-Grunt probe to the Martian moon Phobos, Russia's first inter-planetary probe since its Mars-96 probe failed to enter orbit and broke up in 1996.