The U.S. government’s move to put South Korea -- a non-nuclear ally--in the same company as countries like China or North Korea has unsettled politicians in Seoul

WASHINGTON/SEOUL (Reuters) - The U.S. Department of Energy has designated ally South Korea a "sensitive" country, a spokesperson said on Friday, after the South Korean president briefly imposed martial law and amid talk of Seoul potentially developing nuclear weapons.

The US added South Korea to a list of so-called sensitive countries for energy cooperation in January after a security breach came to light, according to South Korea’s Foreign Ministry.