During the tumultuous 1980s, then President Oscar Arias authored a regional peace plan in 1987 that served as the basis for the Esquipulas Peace Agreement. Arias' efforts earned him the 1987 Nobel Peace Prize. Subsequent agreements, supported by the United States, led to the Nicaraguan election of 1990 and the end of civil war in Nicaragua. Costa Rica also hosted several rounds of negotiations between the Salvadoran Government and the Farabundo Marti National Liberation Front (FMLN), aiding El Salvador's efforts to emerge from civil war and culminating in that country's 1994 free and fair elections. Costa Rica has been a strong proponent of regional arms limitation agreements.