Javier Milei
AFP

Argentina's libertarian President Javier Milei left Monday on a trip to Israel, which he sees as a key ally, and the Vatican where he will meet with Pope Francis.

The 53-year-old Milei, an outsider who rode a wave of fury against Argentina's traditional parties to win power, left on a commercial flight accompanied by his sister Karina, who is his closest aide, and Foreign Minister Diana Mondino.

It is his first official trip, aside from a whirlwind stop at the Davos economic forum in Switzerland last month where he delivered a fiery speech slamming socialism, feminism, and social justice.

Milei has presented himself politically as an ally to Israel, and has said he is open to moving Argentina's embassy from Tel Aviv to Jerusalem.

On Tuesday he will visit the Western Wall in Jerusalem, the holiest place where Jews can pray, before meeting Israeli Prime Minister Benjamin Netanyahu on Wednesday.

Milei will also visit a kibbutz and meet families of the hostages taken by Palestinian militant group Hamas.

Self-described "anarcho-capitalist" Milei was raised in a Catholic family but has spoken of his more recent study of the Torah, the book of Jewish scripture.

Right after his November election, he visited the tomb of a revered rabbi in New York, a popular spiritual pilgrimage destination for some Jews.

Argentina's Jewish community, at 250,000, is one of the largest in Latin America.

After visiting Israel, the Argentine delegation will be joined by three ministers for a visit to Rome on Friday, where Milei will meet Prime Minister Giorgia Meloni.

Milei will have a private audience with his compatriot Pope Francis on February 12, the Vatican said.

Before his October election, Milei had referred to Francis as "the evil one," "nefarious," and an "imbecile" who "promotes communism".

However Milei has since watered down much of his more fiery rhetoric against some of his favored campaign targets -- including the pope, and major trade partners such as Brazil and China.

He and the pope appeared to reconcile -- at least publicly -- when Francis called to congratulate the libertarian president on his election.

Milei is expected to repeat an invitation for Francis to visit Argentina. The 87-year-old pope has not been to his homeland since being named head of the Catholic Church in 2013.

During his trip to Italy, Milei will also attend a Sunday mass in St Peter's Basilica for the canonisation of "Mama Antula" (1730-1799), Argentina's first female saint, over which Francis will preside.