LA PAZ — Bolivia's interim president, Jeanine Anez, began on Wednesday trying to fill the power vacuum left by Evo Morales's abrupt resignation as the former leader denounced what he described as a "sneaky coup."

Anez, 52, declared herself interim president on Tuesday before her claim was endorsed by the constitutional court, arguing that her succession was necessitated by the resignations of those above her in the government hierarchy.

As well as Morales, Bolivia's vice-president, Senate president and speaker of the lower house of Congress had also resigned, leaving Anez as the most senior figure still in office.

Bolivia has been in political turmoil since a controversial Oct. 20 election in which Morales was awarded a fourth term as president.

Opposition figures cried foul claiming electoral fraud and an audit by the Organization of American States (OAS) found clear evidence of vote count manipulation.

Seven people have died in more than three weeks of protests.

Anez, previously the Senate vice-president, tried to gain support for her appointment but failed to reach a quorum as senators from Morales's Movement for Socialism (MAS) boycotted Tuesday's session.

Many senators stayed away amid blockades and continuing protests by Morales supporters.

"We want to call new elections as soon as possible," Anez told Congress, with only Morales opponents present.

"It's a commitment we have made to the country and of course, we will fulfill it," she said.

She has previously said she expects the new government to be installed by January 22.

Tweeting from exile in Mexico, Morales immediately condemned what he called "the sneakiest, most nefarious coup in history."

He called Anez "a coup-mongering right-wing senator" who had "declared herself... interim president without a legislative quorum, surrounded by a group of accomplices."

Security forces fired tear gas in street clashes in La Paz immediately after the Congress session on Tuesday.

Carlos Mesa, the centrist candidate defeated by Morales in the tainted elections, tweeted his congratulations to Anez.

Powerful opposition figure Luis Fernandez Camacho, regional leader in the eastern department of Santa Cruz, announced he had lifted strikes and blockades called three weeks ago in protest at Morales's disputed re-election.

Morales resigned after losing the support of the security forces, leaving the country suddenly rudderless. Dozens of officials and ministers also stepped down, some seeking refuge in foreign embassies.

On Tuesday, Morales vowed to continue "the struggle" after arriving in Mexico where he has been granted political asylum.

He thanked left-wing ally and Mexico President Andres Manuel Lopez Obrador, saying "he saved my life," and vowed to remain in politics despite having left his homeland.

Grinning and waving as he left the Mexican military plane that had picked him up from Bolivia late Monday, Morales was welcomed by Foreign Minister Marcelo Ebrard.

On Monday, the armed forces pledged to help police take back Bolivia's streets from violent groups that have wreaked havoc since the controversial election that saw Morales win an unconstitutional fourth term.

Morales was leading but not by enough to gain outright victory until a sudden unexplained 24-hour freeze of the count resumed with the socialist leader in a much better position than before.

Security forces deployed in La Paz on Tuesday, where Morales supporters marched through the center to congregate in San Francisco Square near the Congress.

Bolivia's attorney general, Juan Lanchipa, said on Tuesday seven people had died in unrest since the election, raising the previous toll of three.

The United States meanwhile warned its citizens against travel to Bolivia, ordered its diplomats' family members to leave and authorized non-emergency employees to depart due to the unrest.

Morales, 60, a former coca farmer who was Bolivia's first indigenous president, said his opposition rivals, Mesa and Camacho, "will go down in history as racists and coup plotters."

He was Latin America's longest-serving leader until Sunday.

Morales had initially tried to hold onto power and called new elections following the OAS audit but that failed to quash the protests against his rule. — AFP