Vice President Jorge Quiroga, 41, will formally assume the presidency when Banzer steps down on the country's Independence Day, Minister of Information Manfredo Kempff said from Miami, where he had missed his plane back to Bolivia.
Kempff had been visiting Banzer in Washington, where the 75-year-old president is being treated at Walter Reed Army Medical Center for lung cancer that has spread to his liver.
The statement came two days after Kempff said Banzer would return to Bolivia to participate in the country's Independence Day festivities and deliver his annual state-of-the-nation address. It was not immediately clear whether Banzer's condition or outlook has worsened since then.
Kempff said Banzer is doing well but decided that he couldn't govern from a hospital bed. Banzer will come back to Bolivia on Aug. 6 to deliver his resignation speech from the southern colonial town of Sucre, and then return to the United States for more chemotherapy, the information minister said.
Quiroga has been serving as acting president since Banzer, a heavy smoker, left Bolivia on July 1 to travel to the United States. At the time, Banzer said he was going for spine treatment, a trip that was supposed to last 12 days. But doctors diagnosed Banzer's cancer and said the president needed special medical treatment for at least 30 days.
In recent days, leading Bolivians had been calling on the president to step down and formally hand power to Quiroga. Some had expressed concern that power struggles within Quiroga's party, as well as rising social discontent, could lead to a power vacuum within the government.
But Kempff said Banzer's decision was not influenced by this pressure.
"The president is resigning voluntarily, without pressure from anybody," Kempff said.
Banzer, whose term was to have ended on Aug. 6, 2002, is not held in particularly high regard by many in Bolivia, and his popularity ratings have remained low ever since he assumed office four years ago.
A dictator from 1971 to 1978, Banzer re-entered politics after Latin American dictatorships went out of style this time, as a democrat. After running in every democratic election in the 1980s and '90s, Banzer finally won the presidency in 1997.
Supporters say he has done more to strengthen Bolivian democracy than any of his political predecessors, pointing particularly to his success in eradicating coca, a traditional leaf in Andean society that is also the base for cocaine.
Critics, however, contend Banzer never lost his autocratic streak, saying that even as a democrat he abused human rights, succumbed to corruption and failed to represent his impoverished, indigenous constituents.
An estimated 60 percent of this landlocked nation of 8 million people live in poverty, which has worsened under Banzer's tenure. Th gap between rich and poor remains wide, with just a small, predominantly Caucasian sector of Bolivian society enjoying material comforts.
Banzer hails from Concepcion, a sleepy ranching town in Bolivia's eastern department of Santa Cruz. Bound for a career in the military, he went to the Bolivian Army Military High School in La Paz, graduating as a cavalry lieutenant.
Banzer's lengthy oft-criticized as submissive relationship with the United States began when he was sent to the U.S. Army's School of the Americas in Panama. He received more U.S. training at Fort Hood, Texas, in 1960, and after commanding the 4th Cavalry Regiment in Bolivia for several years, was sent to Washington as a military attache.
By VANESSA ARRINGTON
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