Mexico has threatened to take Bolivia to the International Court of Justice over what it calls harassment of its diplomatic mission in La Paz, after its embassy sheltered some 20 officials from the former government.
The two countries have been in a spiralling spat since Mexico granted asylum to Bolivian ex-president Evo Morales, who resigned on November 10 in the face of mass protests, and granted refuge to top officials from his leftist government at its embassy.
Mexico accuses Bolivia's new interim government of responding with a campaign of "harassment and intimidation" by deploying a large contingent of police and intelligence officers outside the embassy. That move, according to Mexico, violates the 1961 Vienna Convention on the protected status of diplomatic missions.
Mexican Foreign Minister Marcelo Ebrard said his staff would file a complaint later Thursday with the International Court of Justice in the Hague.
"We are simply proposing that the integrity of our diplomatic installations, which are Mexican territory, be respected and preserved... as well as that of the people inside," he said.
He called for the international community's help to resolve the "emergency."