US President Joe Biden on Monday called on Myanmar's military to relinquish power immediately after they seized power from Aung San Suu Kyi's ruling party while simultaneously ordering a review to consider re-imposing sanctions lifted after the nation's transition to democracy. Biden is threatening to slap new sanctions on Myanmar, also known as Burma, after a coup that saw the military arrest the civilian leaders of its government. Myanmar has been a US democracy promotion project for decades, though there have been recent and serious concerns about its backsliding into authoritarianism. In a White House briefing Monday, press secretary Jen Psaki told reporters the statement from Biden was "a message to all countries in the region." "The military's seizure of power in Burma, the detention of Aung San Suu Kyi and other civilian officials, and the declaration of a national state of emergency are a direct assault on the country's transition to democracy and the rule of law," Biden said in a written statement. "In a democracy, force should never seek to overrule the will of the people or attempt to erase the outcome of a credible election. For almost a decade, the people of Burma have been steadily working to establish elections, civilian governance, and the peaceful transfer of power. That progress should be respected." He noted that the US had removed sanctions on Burma after its transition to democracy but that it would not hesitate to restore them. "The reversal of that progress will necessitate an immediate review of our sanction laws and authorities, followed by appropriate action," Biden said. "The United States will stand up for democracy wherever it is under attack." Calls are growing for the release of Myanmar's Aung San Suu Kyi a day after a military coup, which has seen hundreds of MPs held against their will. Suu Kyi has not been seen in public since she was detained by the military. It took power after declaring a state of emergency, accusing Suu Kyi's party of fraud over its election win. Suu Kyi's party, the National League for Democracy (NLD), demanded her immediate release on Tuesday. It has also called upon the military to accept the results of the November election, which saw the NLD win more than 80% of the votes. There have been no official statements on Suu Kyi's exact whereabouts since she was detained in pre-dawn raids on Monday. But unnamed sources from within the NLD have said both she and President Win Myint were being held under house arrest. — Agencies