in power. Except for a five-month interlude during which his half-brother held the presidency, the armed forces remained in control of the Presidential Palacio Quemado until 1982. In 1971 Siles opposed the right-wing coup of general Hugo Banzer, prompting an irreversible break with Estenssoro, who supported the coup. In 1971 Siles formed the Leftwing Revolutionary Nationalist Movement (Movimiento Nacionalista Revolucionario de Izquierda, MNRI), beginning a steady leftwards drift. The 1978–1982 democratic false starts After the 1978 democratic opening, Siles returned to Bolivia and formed a grand alliance of the left with the Revolutionary Left Movement, the Communist Party, and others. Together, they formed the Democratic and Popular Union (UDP), which triumphed in the 1978, 1979, and 1980 general elections, mostly as a result of a serious erosion of support for Estenssoro. The 1978 election was annulled due to massive fraud in favor of the official military candidate, General Juan Pereda, though exit polls showed Siles would have won handily had the election been conducted honestly. The 1979 contest remained inconclusive because no candidate received 50% of the vote, and Congress elected Wálter Guevara a temporary president. Siles finished first in 1980, but came up short of a majority. Days before Congress was due to convene to choose a winner, the army launched the bloody coup of 17 July 1980, which installed a reactionary (and cocaine-tainted) dictatorship of General Luis García Meza. Siles escaped to exile in Peru by crossing Lake Titicaca on a boat. He returned in 1982, when the military's experiment had run its course and the Bolivian economy was on the verge of collapse. Second presidency (1982–85) With its reputation badly damaged by the excesses of the 1980–82 dictatorship, the military faced two options—call new elections, or accept the 1980 results. By this time, however, it was obvious that the country would crumble into civil war before new elections could be held. Under the circumstances, the military announced in September 1982 that to spare the expense of new elections and avoid further unrest, it would reconvene the legislature elected in 1980 and accept whomever it chose as president. Congress reconvened on 23 September and reconfirmed the 1980 election results. On 5 October, it overwhelmingly elected Siles as president. He was sworn into his second term on 10 October, with the MIR's Jaime Paz as his vice-president. In 1983, Siles Zuazo reopened relations with Cuba after the relationship ended