Admiral Vladimir Kuroyedov's remarks, on which he later backtracked, caught both Moscow and Western officials off guard while analysts searched for clues as to why the Russian navy chief would make such a provocative statement.

The nuclear-powered cruiser Peter the Great has been at sea for only seven years and remains the star of most vital Russian operations in northern waters.

It oversaw the failed efforts to save the 118 seamen who perished in the August 2000 Kursk nuclear submarine disaster and has been toured on festive military occasions by Russian President Vladimir Putin.

But Kuroyedov said Tuesday that he had ordered the ship back into port after finding it in deplorable condition during a visit last week.

"The ship is in such a state that it could explode at any moment," the Interfax news agency quoted Kuroyedov as saying.

"The ship's condition is fine in those places where admirals walk, but where they don't go everything is in such a state that it could explode at any moment. This includes the upkeep of the nuclear reactor," Kuroyedov said.

Peter the Great has two nuclear reactors and an arsenal of cruise missiles that can be tipped with nuclear warheads.

Reports said the 26,000-tonne cruiser's flag was lowered in disgrace as it came into port.

But as alarm grew across Russia, Kuroyedov backtracked on his jarring statement, saying he was misquoted by state news agencies, which for their part refused to retract their reports.

"In this particular case, we are not talking about any danger to the nuclear reactor," the RIA-Novosti news agency quoted Kuroyedov as saying.

Even environmental watchdogs who monitor Russia's nuclear arsenal said that Kuroyedov's comments did not seem plausible and must be linked to some internal navy intrigues rather than an actual state of emergency.

"It is just not possible that it should just blow up without a reason," said Nils Boehmer, of the Bellona environment group in Oslo, of the cruiser's nuclear reactor.

"It is ironic that for once Bellona is trying to calm down the story while the Russian navy is talking about a catastrophe," Boehmer said.

Some Russian media speculated Tuesday that Kuroyedov made his comments because of a personal dispute between the navy's top commanders that did not actually reflect the state of the massive warship.

The Kommersant business daily said Peter the Great's commander is a nephew of a retired navy admiral who recently testified in a court case against Kuroyedov for his role in the failed rescue of another Russian nuclear submarine last August in which nine sailors died.

The analysts said that Kuroyedov was trying to deflect attention from that case by focusing his fury on the warship's command in order to save his own job.

"It looks like he (Kuroyedov) is going to be ousted fairly soon," said military analyst Alexander Pashin from the Northern Fleet port town of Murmansk.

"He is scared about his future and amid the panic he is making strange comments that can really only hurt himself," Pashin said.

Peter the Great's call back to port came only weeks after the very same ship oversaw what were billed as Russia's biggest military war games in 20 years -- exercises which saw two intercontinental ballistic missiles fail in a test launch.

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