LIMA, Dec 20 (AFP) - Peru declared Mexico's ambassador to Lima "persona non grata" and ordered him to leave the country on Tuesday, Peru's foreign minister announced, in the latest escalation of tensions between the two nations after Peru ousted Pedro Castillo as president.

The abrupt order, a severe measure in the world of diplomacy, gives Mexico's envoy to the South American country just 72 hours to exit.

The Peruvian government's decision came hours after Mexico's top diplomat announced that his country had granted asylum to the family of Castillo, who faces rebellion charges from behind bars after attempting what critics have labeled a coup on Dec. 7.

Peru's foreign ministry posted on social media that the ejection of Mexican Ambassador Pablo Monroy was due to "repeated statements from the highest authorities of that country regarding the political situation in Peru," a thinly veiled reference to the support Mexico's president has offered fellow leftist Castillo since his ouster by an overwhelming vote of lawmakers and his subsequent arrest.

The Mexican foreign ministry later said it was ordering its envoy home, and said its Lima Embassy would continue to operate normally.

Mexican President Andres Manuel Lopez Obrador sharply criticized last week the removal of Castillo as undemocratic, stressing that he continues to recognize Castillo as Peru's lawful leader.

Speaking at a news conference earlier in the day, Mexico's foreign minister, Marcelo Ebrard, said the government was negotiating safe passage for the family of Castillo, who were inside Mexico's Embassy in Lima.

Ana Cecilia Gervasi, Peru's foreign minister, announced later on Tuesday that safe passage for Castillo's wife and the couple's two children had been formally approved.