Work has already been severely delayed by bad weather and problems with a huge robotic saw used to cut through the submarine's hull.

The Kursk sank on 12 August 2000, after two massive on-board explosions, resulting in the death of all 118 crew.

Only 12 bodies have been recovered, but President Vladimir Putin has promised that all the victims will be given proper burials on land.

The authorities also want to recover the nuclear reactors, and hope to establish the cause of the disaster by examining the wreck.

Bow lifted later

The bow of the Kursk, containing 18 torpedoes and more than 20 cruise missiles, has been separated from the rest of the sunken vessel and is to be raised by Russian naval experts next June.

Dutch contractors leading the operation to salvage the main part of the vessel have left the area until the weather settles, but the Giant 4 barge that will tow the Kursk to Roslyakovo base, north of Murmansk, remains anchored above the wreck.

President Putin promised to recover the bodies of the lost sailors

Divers must attach steel cables from 26 hydraulic jacks on the barge to pre-cut holes in the Kursk's hull.

They must also "seal" the front end of the wreck with a thick metal sheet to stop more water flooding in and destabilising the operation.

The Russian navy initially blamed the sinking on a collision with a Western vessel.

A subsequent investigation suggested the cause was more likely to have been an accident in the torpedo bay.