WASHINGTON (AP) — Little noticed in the warm glow of President Barack Obama's landmark visit to Myanmar was a significant concession that could shed light on whether that nation's powerful military pursued a clandestine nuclear weapons program, possibly with North Korea's help.

Myanmar announced it would sign an international agreement that would require it to declare all nuclear facilities and materials. Although it would be up to Myanmar to decide what to declare, it could provide some answers concerning its acquisition of dual-use machinery and its military cooperation with Pyongyang that the U.S. and other nations regard as suspect.