REUTERS/Liz TasaMEXICO CITY/LIMA, Dec 20 (Reuters) - 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. Mexico's foreign minister took to Twitter on Tuesday night to blast Monroy's expulsion, deriding it as "unjustified and reprehensible." Speaking at a news conference earlier in the day, Mexican 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.

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