Myanmar will release over 450 prisoners, including an unidentified number of political prisoners, ahead of US President Barack Obama’s historic visit to the former isolated nation, officials announced Thursday.

State media said that the prisoners will be freed with the “intent to help promote goodwill and bilateral relationship” days before Mr. Obama’s visit, the first for a sitting US president.

President Thein Sein pardoned more than 500 prisoners in September, including political prisoners and foreigners, ahead of his visit to New York for a gathering of world leaders where he trumpeted his country’s economic and political reforms.

Relations between the US and Myanmar have warmed rapidly since the quasi-civilian government launched reforms, prompting the West to ease sanctions and paving the way for investments, Reuters reports. The US has repeatedly urged the government to free remaining dissidents in exchange for further economic rewards.

Mr. Obama will make the visit on the sidelines of the annual summit of the Association of Southeast Asian Nations in Cambodia as he reinforces his “pivot” to the Asia-Pacific region.