Venezuela on Wednesday withdrew its ambassador from Brazil and froze ties with its southern neighbor in response to president Dilma Rousseff's removal from office.
The leftist governments of Ecuador and Bolivia also recalled their top diplomats, with Ecuadoran President Rafael Correa calling the senate vote impeaching Rousseff "an apology for abuse and treason."
Venezuela's foreign ministry condemned Rousseff's removal as a "parliamentary coup d'etat."
Venezuela "has decided to definitively withdraw its ambassador in the Federal Republic of Brazil, and to freeze political and diplomatic relations with the government that emerged from this parliamentary coup," it said in a statement.
Rousseff, 68, was convicted by 61 of 81 senators of illegally manipulating the national budget.
The vote ended 13 years of leftist rule in Latin America's biggest economy, depriving Venezuela's socialist leaders of an important ally.
It comes as Venezuela's President Nicolas Maduro finds himself under mounting pressure to submit to a recall election amid a devastating economic crisis.
The opposition has called for a massive march in Caracas on Thursday, raising the stakes in a volatile showdown.
In Ecuador, president Correa took to Twitter to vent his anger about Brazil.
"Never will we condone these practices, which recall the darkest hours of our America," Correa wrote, a reference to military dictatorships of the past.
Ecuador's foreign ministry called Rousseff's removal "a flagrant subversion of the democratic order in Brazil."
Bolivian president Evo Morales announced the recall of ambassador Jose Kim after threatening to do so Tuesday should Rousseff be removed from office.
He earlier condemned on Twitter what he called a "parliamentary coup against Brazilian democracy."
"We stand with Dilma, Lula and the population in this difficult time," Morales wrote, adding Rousseff's mentor and predecessor, former president Luiz Inacio Lula da Silva, who is facing corruption charges.
Bolivia's foreign ministry confirmed the recall in a statement, saying that the government "calls on all the countries of our region to reject these 'soft' blows to the state ... provoked by an opposition unable to achieve enough votes to form a government."