Bolivian Senator Jeanine Anez declared herself interim president of the South American country in Congress on Tuesday despite a lack of a quorum to appoint her in a legislative session boycotted by lawmakers from former president Evo Morales' leftist party.

Morales landed in Mexico on Tuesday pledging to keep up his political "fight" after he and his vice president resigned two days earlier amid protests over the disputed October 20 election.

What did Morales say?

Morales thanked Mexico for "saving his life" as he arrived to take up asylum in the country. He repeated his accusation that his rivals had ousted him in a coup after violence broke out following a disputed election last month.

"As long as I am alive, we will remain in politics. As long as I am alive, the fight continues," Morales told reporters after disembarking the plane, dressed in a blue short-sleeved shirt. He was met by Mexican Foreign Minister Marcelo Ebrard.

Morales was then whisked away in a military helicopter, television footage showed. Mexican officials have not said where he will stay, citing security concerns.

Opposition's Anez declares herself interim president

Anez assumed temporary control of the Senate late on Tuesday, putting her next in line for the presidency. Lawmakers of Morales' Movement for Socialism party were not present when she made the announcement.

Clashes broke out in the streets of the Bolivian capital after Anez's declaration. Police and soldiers fired tear gas to disperse angry Morales' supporters after they tried to reach the Congress building. 

Morales' resignation still needed to be approved by both houses of Congress. Lawmakers failed to get the quorum for an assembly session on Tuesday.

Anez also needed to be approved as president of the Senate, but she said that lawmakers loyal to Morales declined to be part of the session and that Bolivia could not be left in a power vacuum.

Morales' dramatic flight to Mexico

Morales arrived in Mexico after taking off from the central Bolivian town of Chimore, a stronghold of his supporters and where the country's first indigenous president retreated as his 14-year rule imploded. But Morales' journey was far from simple.

Takeoff was delayed, with supporters surrounding the airport. Then the plane was denied permission to refuel in Peru, Ebrard said, so it diverted to Paraguay, a stop which he said Argentine President-elect Alberto Fernandez helped arrange.

Ebrard had earlier tweeted a photo of Morales alone in the jet with a downcast expression, displaying Mexico's red, white and green flag across his lap.

In a region divided along ideological lines over Morales' fall, Mexico's government has supported his accusations of a coup. U.S. President Donald Trump meanwhile said that the resignation was a boost for democracy.

Paraguayan President Mario Abdo said on Tuesday his country had also been willing to grant political asylum to Morales, though he disagreed with accusations of a coup.

"If he resigned, it is not a coup. He resigned," he said.

The Brazilian government on Tuesday issued a statement rejecting the claim of a political coup in Bolivia, underscoring the Organization of American States's (OAS) stance that there was fraud in the October 20 general elections in the country. 

"The Brazilian government entirely rejects the claim that there was a 'coup' in Bolivia," the statement said. 
  
"The resignation of Evo Morales paved the way for the preservation of the democratic order, which would be threatened by the permanence in power of a president benefited by electoral fraud. The constitutional process is being preserved in its entirety in Bolivia," it said.

(With input from Reuters, Xinhua)