A British magazine on military affairs, Jane's Defence Weekly, says North Korea is developing and deploying at least two new ballistic missile systems that may have sufficient range to hit the United States.

In an article Wednesday, Jane's said the two new systems appeared to be based on a decommissioned Soviet submarine-launched ballistic missile, the R-27.

The article added that the North had acquired the relevant know-how during the 1990s from Russian missile specialists and by buying 12 former Soviet submarines that had been sold for scrap metal but retained key elements of their missile launch systems.

The weekly said the development and deployment of such missiles would fundamentally alter the missile threat posed by the communist North and could finally provide its leadership with the ability to directly threaten the continental U.S.