Russia's Phobos-Grunt spacecraft, which has been stuck in the wrong orbit for more than a month, will not be able to complete its mission, the head and chief designer of the Lavochkin spacecraft construction bureau, Viktor Khartov, said on Tuesday.

"We should admit that Phobos-Grunt has failed to fulfill its main mission of reaching Mars," Khartov told RIA Novosti on the sidelines of a space research conference in Moscow. "This is a fact. Mission Impossible."

Phobos-Grunt, launched on November 9, was designed to bring back rock and soil samples from the Martian moon Phobos. However, it has been stuck in a so-called support orbit since its engines failed to put it on course for the Red Planet.

It is estimated to fall back to Earth in mid-January, Khartov said.

The head of Russia's Federal Space Agency (Roscosmos), Vladimir Popovkin, has said the probe will break up during reentry into the atmosphere and none of the fragments are likely to reach Earth.

That includes the spacecraft's 7.5 tons of fuel, which are stored in aluminum tanks that are bound to explode upon reentry.

But Khartov said on Tuesday some parts of the spacecraft with high-temperature protection were likely to reach Earth, including Grunt's return capsule.

A special commission has been created to analyze the causes of the mission failure. Attempts by Russian and European specialists to establish steady contact with the troubled spacecraft have failed.

Khartov said experts would keep trying to contact Phobos-Grunt until it enters the atmosphere.

Attempts are still being made to raise the spacecraft's orbit in order to secure better conditions for establishing communication with it, he added.

Source: RIA Novosti