Mexico threatened Thursday to take Bolivia to the International Court of Justice (ICJ) over what it calls harassment of its diplomatic mission in La Paz, after its embassy sheltered some 20 officials from the former President Evo Morales' government.

The two countries have been in a spiraling spat since Mexico granted asylum to Morales, who resigned on Nov. 10 in the face of mass protests, and granted refuge to top officials from his leftist government at its embassy.

Since right-wing interim president Jeanine Anez took over from Morales, the Bolivian authorities have issued arrest warrants for four of the ex-officials inside the Mexican Embassy, accusing them of "sedition" and "terrorism." Since Nov. 15, a group of ex-cabinet ministers and others loyal to former Morales have sought refuge at the Mexican Ambassador's La Paz residence. Morales has relocated to Argentina and says he plans to stay involved in politics in neighboring Bolivia, while some former top aides remain holed up in the Mexican ambassador's residence.

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.