The head of Russia's state space agency, which has suffered a series of recent setbacks, has been hospitalised with a head injury, reports said Sunday.

Vladimir Popovkin will stay in the hospital for several days, an agency spokeswoman told AFP adding that he "was taken to the hospital due to a worsening of his health condition and received emergency care" on Wednesday.

She added that Popovkin was feeling physically and emotionally exhausted due to work and constant travel, but that his condition is now stable.

Kommersant daily, citing its own sources, said Popovkin felt faint and collapsed on the stairs of the space agency on Tuesday, hitting his head on the marble railing.

Muckraking Life News website said the space chief was brought to the military hospital at 6:00 am with large wounds to his head and a concussion. He was put in the neurosurgical wing.

Popovkin, 54, became the head of Roscosmos in April 2011, replacing Anatoly Perminov and vowing to make the agency more economically viable.

However the agency continued to face mishaps under his guidance, most recently losing an ambitious probe to Mars called Phobos Grunt and a crucial Progress spacecraft that carried supplies to the International Space Station.

The Russian agency is also under pressure to bear the full brunt of responsibility for carrying cosmonauts to the ISS after the United States retired its Space Shuttle program.