President Barack Obama has renewed sanctions against Myanmar even though he said it had made some progress on reforms. Obama, who made a groundbreaking visit to Myanmar in 2012, announced the renewal Thursday in a letter to Congress. The sanctions bar American companies and citizens from investing in the country formerly known as Burma. They also mean Americans cannot do business with Myanmar leaders identified as having repressed pro-democracy sentiment in that nation formerly run by a tough military junta. On Thursday Obama said Myanmar has made significant progress in a number of critical areas. These include the release of over 1,100 political prisoners, progress towards a nationwide ceasefire, legalization of unions, steps to improve the country's labor standards, and allowing greater freedom of association and expression, Obama said. But the United States had to renew the trade and business sanctions because Myanmar still poses "an unusual and extraordinary threat to the national security and foreign policy of the United States." Obama said: "The political opening remains nascent, and concerns persist regarding ongoing conflict and human rights abuses in ethnic minority areas, particularly in Rakhine State, and the continued role of the military in the country's political and economic activities."