The inter-Korean maritime border in the Yellow Sea has reportedly been called legally indefensible by U.S. officials, including former Secretary of State Henry Kissinger.

Bloomberg reported that then-Secretary of State Henry Kissinger wrote in a 1975 classified cable that the unilaterally drawn Northern Limit Line (NLL) was clearly contrary to international law. He noted that North Korea did not accept the NLL.

Two years earlier, U.S. Ambassador Francis Underhill said in another cable that many nations could view South Korea and its ally, the U.S., as in the wrong if clashes occurred in disputed areas along the boundary.

Bloomberg quoted a Japanese security expert as saying that the NLL was drawn immediately following the 1953 armistice by then-U.N. Commander Mark Clark to stop disruptions to the fragile armistice Clark oversaw.