North Korea fired a ballistic missile into waters off its east coast on Sunday, its second missile test in a week, which South Korea said dashed the hopes of the South’s new liberal government for peace between the neighbors.

A South Korean military official said the missile appeared to be an upgraded, extended-range version of the North’s solid-fuel submarine-launched missile. The missile fired a week ago flew was liquid-fueled, and flew further.

North Korea has defied all calls to rein in its nuclear and missile programs, even from China, its lone major ally, saying the weapons are needed for legitimate self-defense.

The reclusive state has been working to develop a nuclear-tipped missile capable of striking the U.S. mainland. On Saturday, it said it had developed the capability to strike the U.S. mainland, although Western missile experts say the claim is exaggerated.