Russia's space agency predicts that the fragments of a failed Russian space probe's could fall into the Indian Ocean, far away from any populated areas.

Roscosmos said on Thursday that the Phobos-Ground's debris could fall between Saturday and Monday anywhere along a broad swath between 51.4 degrees north to 51.4 degrees south.

That includes the bulk of the land surface, but spares most of Russia's territory along with Scandinavia and a large part of Canada.

The agency said the mid-point in the three day window at 1448 IST on Sunday when fragments could come crashing down correspond to a place in the Indian Ocean, about 1,700 kilometres west of Jakarta.

Roscomos said, however, that the forecast will be clarified as the probe's orbit draws closer to Earth.