Former president of Bolivia Mr Gonzalo Sanchez de Lozada has blamed drug interests and trade unionists for his ousting.
Mr Sanchez de Lozada resigned on Friday, under pressure from massive protests that left more than 70 dead and 200 injured. He said he fled because he feared his family could be attacked.
He said he planned to continue to lead his party, the Revolutionary Nationalist Movement, saying he would be "very, very active in politics", although he would not run for president again.
"Politics is like a drug, it doesn't treat you well, but you can't stay away from it," he said.
Speaking in Washington, having fled to Miami at the weekend, he urged the United States and multilateral institutions such as the International Monetary Fund to help the former vice president who replaced him, Mr Carlos Mesa.
He made the plea despite claiming Mr Mesa "contributed" to his fall by not supporting him in the final moments of his presidency.
"I am in Washington because I still see very delicate problems for Bolivia, that have not been solved by my resignation. These are problems of national disintegration, of union and corporatist authoritarianism, and of fratricidal violence," he said.
Mr Sanchez de Lozada, a wealthy businessman who was raised in the United States, said that if the Mesa government failed, Bolivia could split in two, with the gas-rich southern Andean provinces "seeking cover from neighbours" and the rest of the country becoming a pariah state dedicated to coca cultivation.
The former president's strongest critics were union and indigenous groups as well as coca farmers, headed by Mr Evo Morales, a socialist who came in second in last year's presidential elections.
Agencies