For more on South Korea's reaction, joining us now is our correspondent Shane Hahm from Seoul.

Q1:  Hi Shane, great to have you. Seoul has been closely monitoring activities in the North and making preparations.  What will South Korea do if Pyongyang goes ahead with another nuclear test?

Q2:  Pyongyang has always objected to the joint military drills by South Korea and the US. How have the two allies responded to the criticism this year?