South Korea official : South Korea ready for nuclear test . Official : Nuclear closure is last time to ready for test . The North Korean Foreign Ministry earlier this week described Obama 's trip as `` a reactionary and dangerous one as it is aimed to escalate confrontation and bring dark clouds of a nuclear arms race to hang over this unstable region . '' Details come as U.S. President Obama visits South Korea .
South Korea official : South Korea ready for nuclear test . Official : Nuclear closure is last time to ready for test . Details come as U.S. President Obama visits South Korea .