Pope Leo leaves on emotional South America tour weeks after surgery

Pope Leo XIV headed to South America on Friday for an emotionally charged reunion with the continent that helped shape his priesthood, three weeks after undergoing lung cancer surgery.

The 71-year-old head of the Catholic Church will in 12 days visit Uruguay, Argentina and Peru in one of the most intense papal foreign trips in decades, meeting political leaders, prisoners, the poor, as well as old friends.

A smiling Leo waved to onlookers before boarding his plane under overcast skies at Rome's Fiumicino airport, with the aircraft taking off shortly after 0600 GMT, according to AFP journalists.

The Church's first US-born pope served for almost two decades in Peru as a missionary, forming a deep attachment to the continent. Leo said on Wednesday that he was looking forward to returning to those countries "so dear to me".

The head of the world's 1.4 billion Catholics said he hoped the trip would "strengthen faith, renew hope, (and) rekindle the fire of charity" in the countries, which share challenges from rising inequality and violence, to demographic falls and the decline of Catholicism.

Despite undergoing an operation on October 13 to remove a cancerous tumour, doctors have given him the all-clear to travel, and the Vatican said no special medical measures were necessary beyond the standard care on papal trips.

Leo begins his trip in Uruguay, Latin America's most secular country -- and one of the wealthiest -- where a tight security operation is in place, with some 5,000 police officers and 1,000 soldiers mobilised.

He will be driven along Montevideo's waterfront promenade in a custom-made popemobile, before meeting left-wing President Yamandu Orsi and receiving the keys to the city.

"I have family members who plan to go to the waterfront to watch him pass," Janet Rodríguez, 47, told AFP.

"I won't be going, as I'm not religious. But it's great that someone of such importance is coming," she said.

Cardinal Daniel Sturla, archbishop of Montevideo, told AFP there was "widespread interest in the pope's visit that goes well beyond the confines of the Catholic Church", with tickets for masses in Paysandu and Florida quickly running out.

The liberal nation is at odds with the centuries-old institution on same-sex marriage, abortion and euthanasia -- which was legalised last year -- and Leo is expected to appeal to protect life as well as traditional family values.

Uruguay has the highest suicide rate in Latin America and the pope may talk about mental health, particularly when visiting the Casavalle neighbourhood in Montevideo, notorious for high levels of poverty and extreme violence.

The pope will travel Sunday to Argentina, the homeland of his predecessor Pope Francis, who disappointed many Argentinians by not returning to visit during his papacy.

Leo's trip is seen as a double homecoming of sorts, US-based Vatican expert Christopher White told AFP.

"History's first Latin American pope, Francis, never returned to his homeland. Leo, a Peruvian citizen, now carries forward that mantle and legacy," said White, author of a book on Pope Leo.

The South America trip culminates in Peru, and Leo's arrival there on Wednesday will be "a moment full of symbolism and emotion", he said.

The country has been gripped by pope fever. In Lima, vendors are selling T-shirts and rosaries with his image on them, while Leo bread is on sale in bakeries. Inmates in a women's prison are crafting dolls in his likeness.

A towering, 14-metre (46-foot) statue of Leo has also been erected in the port city of Callao, which he is to visit.

The trip will take him to the former Inca capital of Cusco and the Amazon rainforest, but the pope will also revisit his former life as Robert Francis Prevost, from a supper with priests from his old diocese of Chiclayo to a private visit to a chapel he helped rebuild.