WASHINGTON — National Security Adviser Wi Sung-lac has said he will navigate the possibility of establishing a separate bilateral agreement with Washington for Seoul's drive to build nuclear-powered submarines. Wi made the remarks as he arrived in Washington on Tuesday, about a month after the allies released a joint fact sheet outlining trade and security agreements reached during the second summit between President Lee Jae Myung and U.S. President Donald Trump. "In the case of Australia, an exception was granted in accordance with Section 91 of the U.S. Atomic Energy Act, which requires a separate bilateral agreement," Wi told reporters. "Since we may also need that, I will discuss such a possibility." Wi's remarks were seen as referring to how Australia and the United States signed a bilateral agreement based on the U.S. law that paved the way for them to circumvent an existing bilateral nuclear energy agreement to back Australia's acquisition of nuclear-powered submarines. Currently, South Korea is banned from using nuclear material for military purposes under a bilateral civil nuc