Pope Francis (center) is greeted by Philippine Cardinal Luis Tagle during a welcome ceremony shortly after arriving at a military air base in Manila on Thursday (AFP Photo/Ted Aljibe)
Pope Francis arrived in the Philippines on Thursday for a week-long trip in the Catholic Church's passionate and chaotic Asian heartland that is tipped to attract a world-record papal crowd.
Church bells tolled across the nation as the charismatic pontiff flew into the capital of Manila after a successful trip to Sri Lanka.
Francis smiled as he looked out the window of his plane upon touchdown, and hundreds of children brought to greet him chanted on the tarmac: "Welcome Pope Francis".
Francis has said his two-nation tour is aimed at adding momentum to already impressive growth for the Church in Asia, with its support in the Philippines the benchmark for the rest of the region.
Eighty percent of the former Spanish colony's 100 million people practice a famously fervent brand of Catholicism, and the pope is set to enjoy thunderously enthusiastic crowds throughout his stay.
"Every step he makes, every car ride he takes, every moment he stays with us is precious for us," Archbishop Socrates Villegas, president of the Catholic Bishops' Conference of the Philippines, said as he called on all Filipinos to make an effort to see him.
Hoping for a first glimpse, hundreds of thousands of people gathered on Thursday along the route the pope is scheduled to pass along as he makes his way from the airport to the Vatican's embassy to rest overnight.
"It's a blessing to see the pope. That's why we're here," school teacher Jeannie Blesado, 35, said as she sat on the side the road more than six hours before the pope was due to arrive.
The high-point of his trip is expected to be an open-air mass on Sunday at a park in Manila, with organizers preparing for up to six million people despite a forecast of rain and security concerns.
Organizers have said that, if the crowd is as big as expected, it will surpass the previous record for a papal gathering of five million during a mass by John Paul II at the same venue in 1995.
Francis, who is the fourth pope to visit the Philippines, is also due to visit communities devastated by Typhoon Haiyan, which killed or left missing 7,350 people in 2013.
Pope Francis walks with President Benigno Aquino (3rd right) after arriving in Manila on Thursday (Photo by Gil Nartea/Malacañang Photo Bureau)
Church officials have said one of the main reasons for Francis wanting to visit the Philippines was to make a "mercy and compassion" trip to meet survivors of the typhoon.
On Saturday, he is scheduled to deliver a mass to tens of thousands of people in Tacloban, one of the worst-hit cities in the central Philippines, and have an intimate lunch with 30 typhoon survivors.
The main scheduled events on Friday included a state welcome at the presidential palace, a mass at Manila Cathedral and a meeting at a shopping mall with thousands of families.
Authorities have expressed major concerns over the pope's security in the Philippines, where attempts have been made to kill visiting pontiffs twice before.
Nearly 40,000 soldiers and police are being deployed to protect Francis in what Philippine military chief General Gregorio Catapang described as a "security nightmare".
Potential stampedes from the giant crowds, as well as the threat of Islamic militants or lone-wolf assailants are among the concerns.
On the first papal visit to the Philippines in 1970, Bolivian painter Benjamin Mendoza donned a fake priest's cassock and swung a knife at Pope Paul VI as he arrived at Manila airport.
Paul VI was wounded but continued his trip without disclosing his injury.
One week before John Paul II's 1995 visit, police uncovered a plot by foreign Islamist extremists to kill him by bombing his Manila motorcade route.
Philippine President Benigno Aquino made a nationally televised address this week specifically to highlight the security threats for the pope and call on all Filipinos to help protect him.
"I ask you, do you want history to record that a tragedy involving the pope happened in the Philippines," Aquino said.
Adding to the concerns, the 78-year-old pontiff has insisted he will not travel in a bullet-proof "popemobile" during his big events so he can be closer to the faithful.
The pope flew out of Sri Lanka on Thursday morning, a day after one million people gathered to hear him give mass in what police said was the biggest public celebration ever for the capital of Colombo.
His visit, which began on Tuesday, came days after an election that exposed bitter divisions on the island and saw the surprise victory of Maithripala Sirisena over strongman president Mahinda Rajapaksa.
Archbishop Malcolm Ranjith said the pope had brought "great joy" to the island as it struggled to recover from civil war. AFP