The accident which crippled the Russian submarine apparently happened on Saturday, a day earlier than previously believed, Norway's Foreign Ministry said yesterday.
An official Russian report on the Kursk was handed to Norway yesterday, a Ministry spokesman, Mr Karsten Klepsvik, said.
"It states that the accident happened on August 12th," he said. "The vessel was located on Sunday." The extra day would add to problems of low oxygen for the sailors trapped in the stricken Kursk.
Mr Klepsvik quoted the report as saying the submarine sank "because of a lack of buoyancy in the air-tight hull".
The report implied that an explosion had taken place aboard and did not refer to the theory put forward by Russian officials, that it had collided with a foreign submarine. "That possibility is not mentioned," Mr Klepsvik said.
The report also stated there was no sign of damage to the vessel's nuclear power plant and that there were no leaks of radioactivity into the atmosphere.
Mr Klepsvik said Norway's Foreign Ministry had requested a report from Moscow about the accident.
There was speculation yesterday that movement would have been impossible on board the stricken Kursk as the crew waited in semi-darkness for sounds of rescue. Sensor displays, gauges and even the radio were thought to be out of action. Oxygen was likely to be at a minimum, and the crew could already be having difficulty breathing. With the air-conditioning not functioning, it was likely to be freezing on board.
Last night a former British nuclear submarine commander, Capt Mike Finney, said: "It is very difficult to gauge the crew's state of mind or health. We can only speculate as we don't have details of the damage . . . or the design of the vessel. But it is not a place you would want to be.
"However, if the conditions on board support life, a waiting game might be the sensible one to play until weather conditions allow support ships to provide the men with a controlled escape."