operated a mission of the Provisional Government of Bangladesh. After the liberation of Bangladesh in December 1971 and the withdrawal of Indian troops in March 1972, the United States formally recognized the newly independent country on 4 April 1972, and pledged US$300 million in aid. Herbert D. Spivack was the principal American diplomatic officer in Dhaka at the time. Four days later, the United States and Bangladesh agreed to establish diplomatic relations at the embassy level. The consulate-general was officially upgraded to an embassy on 18 May 1972. Relations between Bangladesh and the American-led Western world dramatically improved in the late 1970s, when President Ziaur Rahman reversed the socialist policies of the first post-independence government and restored free markets. In 1983, military ruler Lieutenant General Hussain Muhammad Ershad was invited to the White House for talks with President Ronald Reagan. President Reagan praised Dhaka for its role in the Cold War, stating "the United States wishes to applaud Bangladesh, a member of the nonaligned movement, for its constructive approach to issues of regional and global concern. To cite only a few examples: Bangladesh clearly manifested its courage and resolve in its unswerving responses to aggression in Afghanistan and Kampuchea. It also took the lead in establishing the South Asian Regional Cooperation Organization, a body designed to build a more prosperous and stable region for the people of South Asia. Bangladesh's foreign policy has exhibited an activism, moderation, and force of moral conviction which has earned the respect of the world". The United States has been one of Bangladesh's principal development partners since independence, providing over US$6 billion through USAID since 1972. It has helped set up important infrastructure in the country, including NASA assistance for the Space Research and Remote Sensing Organization (SPARRSO) and a TRIGA research reactor in the Bangladesh Atomic Energy Commission. Bangladeshi Nobel Laureate Muhammad Yunus has been awarded the US Presidential Medal of Freedom and the US Congressional Gold Medal, the highest civilian honours of the United States. Present relations Bangladesh is a major American ally in South Asia. The two countries have extensive cooperation on matters of regional and global security, counter terrorism and climate change. Bangladesh has been a key participant in the Obama administration's main international development initiatives, including food security, healthcare and the environment. A strategic dialogue agreement was signed between the two countries in 2012. The US Ambassador to Bangladesh Marcia