Russia, China, Uruguay and Argentina also expressed support for Evo Morales.
Mexico which has offered Bolivian President Evo Morales political asylum on Monday after his forced resignation in the wake of a coup, while thousands of pro-Morales protesters were marching towards the nation's legislative assembly.
"It's a coup because the army requested the resignation of the president, and that violates the constitutional order of that country," Mexican Foreign Minister Marcelo Ebrard said.
Ebrard recalled that Mexico was known for respecting the domestic affairs of any nation, as well as granting the right to political asylum for whoever suffered from political persecution.
He reported that Morales did a formal request following Mexico's offer of asylum, and granted the status over "humanitarian reasons, and the emergency situation currently experienced in Bolivia."
Russia also showed strong support for Morales, lamenting "an orchestrated coup."
"We are alarmed by the dramatic developments in Bolivia, where the wave of violence, unleashed by the opposition, prevented the completion of Evo Morales's presidential mandate," said Russia's Foreign Ministry in a statement.
China also "hopes to see that both parts can find a political solution in Bolivia as soon as possible so political stability would return."
Morales repeated on Monday that he was the victim of a conspiracy by enemies including election rival Carlos Mesa and protest leader Luis Fernando Camacho. "The world and our Bolivian patriots repudiate the coup," he tweeted.
Argentine President-elect Alberto Fernandez echoed Morales' denunciations, as well as Uruguay.
The departure of Morales, Bolivia's first indigenous president and part of a wave of leftists who dominated Latin America's politics at the start of the century, followed weeks of violent protests by far-right sectors pretexting fraud claims at the Oct. 20 re-election.
In a redrawing of Latin America's political landscape, the left has regained power in both Mexico and Argentina, though powerhouse Brazil still retains a far-right government.
Bolivia under Morales had one of the region's strongest economic growth rates and its poverty rate halved.
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