During his presidency, Kennedy congratulated Algeria after it had won its independence from the French in 1962. Prime Minister Ben Bella visited President Kennedy on October 15, 1962, one day before the Cuban Missile Crisis started. However, Algeria cut off diplomacy in 1967 because of the Arab-Israeli War, since it supported the Arab countries while the United States was on the Israeli side. In 1971 Natural Gas Corporation from El Paso and Algerian Sonatrach signed an 25 years long agreement on export of 15 billion cubic meters of natural gas starting from 1974. President Nixon was able to reestablish relations and President Boumédiène visited the United States on April 11, 1974. During the Iranian hostage crisis, Algeria mediated negotiation between the United States and Iran. The Algiers Declarations was signed on January 19, 1981. Iran released 52 American hostages on January 20, 1981. 9/11 After the September 11 attacks on the World Trade Center and the Pentagon, Algeria was one of the first countries to offer its support to the US and continued to play a key role in the struggle against terrorism. It has been working since then closely with the United States to eliminate transnational terrorism. The United States made Algeria a "pivotal state" in the war on terror. One of the major agreements between the two countries allowed the U.S. to use an airfield in Southern Algeria to deploy surveillance aircraft. After this, the U.S. has been more neutral on Algerian government political and civil rights violations. Algeria persists in leading the battle against terrorism in Africa. Mid-2000s–present In August 2005, then-Chairman of the United States Senate Committee on Foreign Relations, Senator Richard G. Lugar, led a delegation to oversee the release of the remaining 404 Moroccan prisoners of war held by the Polisario Front in Algeria. Their release removed a longstanding bilateral obstacle between Algeria and Morocco. In April 2006, then-Foreign Minister Mohammed Bedjaoui met with U.S. Secretary of State Condoleezza Rice. As of 2007, the official U.S. presence was Algeria is expanding following over a decade of limited staffing, reflecting the general improvement in the security environment. Between 2004 and 2007, the U.S. Embassy moved toward more normal operations and as of 2007 provided most embassy services to the American and Algerian communities. President Bouteflika welcomed President Barack Obama's election and said he would be glad to work with him to further cooperation between the