The U.S. State Department says Washington and Seoul are in close contact over their joint response to North Korea,... after the two Koreas announced their plans for a third Moon-Kim summit in September.<br /> A State Department spokesperson told Yonhap News Agency on Monday that "the improvement of relations between North and South Korea cannot advance separately from resolving North Korea's nuclear program."<br />This comes as Washington continues to press Pyongyang to demonstrate its commitment to denuclearization, such as by declaring a full inventory of its nuclear arsenal. <br />
