The legislation, passed by Congress last month, comes as the United States lifts financial and other sanctions on Myanmar, to reward a political opening engineered by President Thein Sein after decades of military rule.

The US Treasury said that the move will support "stronger institutions to ensure sound economic policy and good governance in Burma" and would support development and help reintegrate the isolated state into the global economy.

At the order of the US president, American representatives will be empowered by the law to support financial assistance from international bodies for Myanmar, which is also known as Burma.

"Implementation of this law will provide the United States with the ability to shape the policies and activities of these institutions in a way that advances reform, good governance, transparency and accountability in Burma," said Deputy Treasury Secretary Neal Wolin.

Obama's action came a week after the United States announced that it would ease a ban on imports from Myanmar, lifting its last major trade embargo against the former pariah state.

The move, which will have to be carried out in conjunction with Congress, comes just over a week after democracy icon Aung San Suu Kyi started a historic visit to the United States by calling for an end to sanctions.