Myanmar has announced it will sign an international agreement that would put the once pariah state under the close scrutiny of UN nuclear inspectors in an apparent move reflecting that it would go beyond democratic reforms.

The agreement will require Myanmar to declare all nuclear facilities and materials, while it can still decide on what to reveal. Still, it could shed light on speculations that the country’s nuclear programme was backed by North Korea, including the acquisition of dual-use machinery and military cooperation with Pyongyang.

While some analysts said it was a “remarkable decision”, Myanmar still has a lot to divulge and international concern will persist until it gives full disclosure of its relationship with Pyongyang, US Senator Richard Lugar said.

Myanmar reassures there’s nothing to be concerned about, despite a record that it had procured nuclear materials from several countries, including Germany, Switzerland and Singapore. Myanmar apparently sought North Korea’s help in 2005 for a nuclear program.

Washington said that military trade between Myanmar and North Korea had been limited to small arms and missiles – a violation of UN sanctions against Pyongyang. The US Navy intercepted North Korean ships en route to Myanmar in 2009 and 2011.

This comes as US President Barack Obama made his historic visit to Myanmar as relations improved with the easing of sanctions following sweeping economic and political reforms spearheaded by President Thein Sein.