The DPRK is facing international condemnation after investigators blamed it for the sinking of the ship, in which 46 sailors died.

Pyongyang has rejected the claim as a "fabrication" and threatened war if sanctions were imposed.

The report - by a team including experts from the US, Australia, Britain and Sweden - concluded that a torpedo had sunk the Cheonan corvette.

The investigators said parts of the torpedo found on the sea floor had lettering that matched a DPRK design.

Defence Secretary Robert Gates said the US was in "close consultation" with the RoK, which would decide what action to take.

Britain, Australia and Japan also expressed anger at the DPRK. UN Secretary General Ban Ki-moon said the report was "deeply troubling".

Pyongyang has said it would send its own inspection team to the RoK, to "verify material evidence" behind the accusation.