Exiled former Bolivian president Evo Morales backtracked on Thursday from a vow to create armed civilian militias similar to notorious 'colectivos' in Venezuela, were he to be allowed back to his homeland.

Morales caused outrage with his comments last weekend, with interim President Jeanine Anez saying his words proved that "peace, reconciliation and democracy were never options for him."

The 60-year-old former trade union leader resigned in November after three weeks of violent protests against his controversial re-election in a poll the Organization of American States said was rigged.

He initially fled to take up asylum in Mexico before moving on to Argentina last month.

On Sunday he told Bolivia's Radio Kawsachum Coca (RKC) -- owned by the coca planters union to which he belongs -- that should he return to his homeland "we will have to organize popular armed militias, as Venezuela has done."

But on Thursday he took to Twitter to retract those comments.

"A few days ago some of my words were published about the formation of militias. I retract those," he said.

"My most profound conviction has been the defence of life and peace."

Venezuela's colectivos -- created by late leftist icon Hugo Chavez -- have been accused by NGOs of carrying out violent oppression against opposition protesters.

On Wednesday, several Venezuelan opposition lawmakers said their vehicles had been shot at by colectivos as they made their way to parliament.

Opposition leader Juan Guaido has led a year-long struggle to unseat left-wing President Nicolas Maduro, who succeeded Chavez when he died.

Morales's words brought condemnation from the UN special envoy to Bolivia, Jean Arnault.

On Wednesday Arnault said the UN "joins in the rejection" of Morales' statement.

Morales tweeted that he didn't want "anything that I've said to be used as a pretext to persecute and repress my brothers and sisters."

His tweet came as soldiers entered the restive region of Chapare, where a few days ago Morales supporters began protests against the interim government, to destroy illegal coca leaf plantations.

Morales has said he intends to return to Bolivia to lead his Movement for Socialism's presidential election campaign ahead of May's vote.

The party's candidate has yet to be announced but the interim government has banned Morales from standing.

An arrest warrant has been issued for Morales should he return to Bolivia.

He is accused of terrorism and sedition over an audio recording in which he allegedly encourages his supporters to lay siege to major cities.