Article published on the 2008-09-11 Latest update 2008-09-11 15:39 TU
US spokesman Sean McCormack said Goldberg would possibly be leaving in the next 72 hours, adding, "We're at the point of considering all our options regarding our relationship."
In a speech on Wednesday, Morales accused US ambassador Philip Goldberg of aiding his opponents, adding that "he should return to his country at once".
"Without fear of the Empire, I declare in front of the Bolivian people that Mr. Goldberg is persona non grata," he added.
Last month, Goldberg met with the governor of Santa Cruz state, Morales' arch-enemy, eliciting protests from the Foreign Ministry.
Morales has been dealing with violence around Bolivia, the repercussions from an ongoing political conflict. He has been trying to reform the country to give the indigenous majority more power, angering conservative governors in five of the nine Bolivian regions.
In Yacuiba, south-east Bolivia, a gas pipeline was blown up on Wednesday, allegedly by anti-government protesters. The act caused a cut in natural gas supplies to Argentina and Brazil.
Relations between the US and Latin America's poorest state have been tense since Morales was elected. Last June, USaid, a US government aid initiative, was expelled from the country.
Thomas Shannon, the US under-secretary of state for Latin American affairs visited La Paz at the end of July to try to resolve the tense atmosphere.