Thousands of mourners paid tribute to Alexander Solzhenitsyn, the former dissident Russian Nobel author, lying in state at the Academy of Sciences in Moscow on Tuesday.

An honour guard stood at the four corners of his coffin, heaped in long-stemmed flowers deposited in twos by Muscovites who filed passed the open coffin, crossing themselves. Many had waited in the endless rain to be admitted.

State television showed Russian Prime Minister Vladimir Putin among the mourners. The former Kremlin chief placed red roses at a wall-sized, black-and-white portrait of Solzhenitsyn. The portrait was flanked by a Russian flag at the end of the academy's vast hall that reverberated with all the trappings of a state funeral.

The former exile but deep patriot had prayed to die at home, his widow Natalya said. He died of heart failure at the age of 89 late Sunday.

Solzhenitsyn's widow and son held vigil, occasionally walking over to lay a hand on the edge of the coffin or bend down to kiss it, Russian television images showed.

Solzhenitsyn, who unflinchingly chronicled the horrors of the Soviet Gulag camps, remains a controversial figure - almost irrelevant to the next generation sucked-forward in Russia's head- long resurgence.

Some mourners held copies of his first revolutionary expose on life in the camps where he spent eight years, One Day in The Life of Ivan Denisovich, miraculous allowed to be published in 1962 by then- Soviet leader Nikita Khrushchev.

Other former political prisoners were also among the mourners Tuesday. "I also went through the horrors of the gulags," said teacher Luydmila Aleksejevna who placed red carnations near Solzhenitsyn's coffin.

"I was 10 years old but I remember it as a shock. It was a revolution, it was all anybody could talk about for weeks," said Masha Lipman, an analyst at the Moscow Carnegie Centre.

But by the 1970s, Russians could once again be jailed for owning a copy of Solzhenitsyn's four-volume Gulag Archipelago, a mass incriminating documentation of the forced labour camps spread along the rail network from the Arctic Solovetsky Islands to Kazakhstan.

Solzhenitsyn's recognition with the Nobel literature prize in 1970, historians suspect, saved him from being re-incarcerated and in an unprecedented move he was expelled by KGB chief Yuri Andropov.

Russia's Vladimir Putin led condolences, calling his death "a heavy loss for the whole of Russia.

German Chancellor Angela Merkel, French President Nicolas Sarkozy, US Secretary of State Condoleezza Rice and Mikhail Gorbachev, the last Soviet President, were among those who remembered Solzhenitsyn as Russia's moral conscience.

Russian newspapers' mourned Solzhenitsyn's passing with blitzing headlines: "A Prophet Has Died In His Homeland," wrote popular daily Komsomolskaya Pravda while tabloid Tvoi Den led in bold black "Alexander The Great."