Uncertainty over the location of the impending crash of Russia's failed Mars probe grew Friday, with an official saying it may end up in the Atlantic and not Pacific Ocean as suggested.

A source in the Russian space industry said the Phobos-Grunt probe would probably re-enter the atmosphere on Sunday evening Moscow time rather than the afternoon slot initially predicted by the Roskosmos space agency.

This meant that "Phobos-Grunt will enter the atmosphere over Argentina and have its fragments splash down in the Atlantic Ocean," the unnamed official told the Interfax news agency.

Roskosmos on Thursday released a complex diagram showing the $165-million craft potentially crashing at any point on Earth south of London and north of the southern-most tip of New Zealand.

The space agency said Thursday it expected some 20 to 30 fragments weighing about 200 kilogrammes (440 pounds) to land Sunday afternoon between the northwestern shores of Madagascar and the east coast of Africa.

But the space source said the probe now seemed destined to begin its fatal descent a few hours later at 8:00 pm (1600 GMT), giving it more time to travel closer to Latin America.

The unmanned Phobos-Grunt lost its course to the Red Planet and its moon Phobos when it became stuck in a low Earth orbit after blasting off from Russia's space centre in Kazakhstan on November 9.

The ambitious and high-stakes project aimed to revive Russia's interplanetary programme and prepare the way for a manned mission to Mars.

But it came to represent one of the more high-profile mishaps in a year littered with unprecedented setbacks in the Russian space programme.

The accident struck less than three months after an unmanned Progress supply ship bound for the International Space Station crashed into Siberia.

Russia also lost three navigation satellites, an advanced military satellite and a telecommunications satellite in the past year.