US President Donald Trump on Monday hailed the resignation of Bolivia's leftist leader Evo Morales as a sign to "illegitimate" regimes and praised the role of the country's military.

"These events send a strong signal to the illegitimate regimes in Venezuela and Nicaragua that democracy and the will of the people will always prevail," Trump said, referring to two other leftist Latin American nations targeted by his administration.

Trump said that the resignation of Morales, Bolivia's first indigenous leader who was seeking a fourth term despite a constitutional prohibition, was a "significant moment for democracy in the Western Hemisphere."

"After nearly 14 years and his recent attempt to override the Bolivian constitution and the will of the people, Morales' departure preserves democracy and paves the way for the Bolivian people to have their voices heard," Trump said in a statement.

"The United States applauds the Bolivian people for demanding freedom and the Bolivian military for abiding by its oath to protect not just a single person, but Bolivia's constitution," he said.

Morales quit on a fast-moving day of events on Sunday after security forces pulled through support for him in the face of public protests and a report by the Organization of American States that pointed to irregularities in voting last month.

People block a street near the main square in La Paz after Evo Morales resigned as president
People block a street near the main square in La Paz after Evo Morales resigned as president AFP / AIZAR RALDES

A State Department official rejected accusations that the Bolivian military staged a coup, calling it a "false narrative."

"You have surely seen statements by Morales and his supporters calling him the victim of a coup, despite the fact that what all these events clearly show is the Bolivian people have simply had enough of a government ignoring the will of its voters," the official said.

He nonetheless voiced hope that the transition would be civilian-led and said the United States was not picking a favorite.

The official said that Bolivian legislators should formally accept Morales' resignation and call new elections.

"We call on the National Assembly to convene, to provide the quorum required and to determine a constitutional transition to new elections as soon as possible," the official said on condition of anonymity.

A formal designation of a coup would require the United States to cut most aid to Bolivia, which had uneasy relations with the United States under Morales, especially over his championing of indigenous coca farmers.