Pope Francis, 87, landed in Muslim-majority Indonesia on Tuesday for a visit dominated by inter-faith ties, at the start of an ambitious four-nation tour that will be the longest of his papacy.

The pontiff left Rome on Monday afternoon and landed in Jakarta just before midday Indonesian time, the first stop in a 12-day voyage that will also take in Papua New Guinea, East Timor and Singapore.

Covering about 32,000km (almost 20,000 miles), the tour – the longest and farthest of his 11 years leading the worldwide Catholic church – will test Francis’s increasingly fragile health. In recent weeks the pontiff has appeared in good spirits.

Catholics represent fewer than 3% of the population of Indonesia, or about eight million people, compared with the 87%, or 242 million, who are Muslim. In the officially secular country, Catholicism is one of six officially recognised religions or denominations, also including Protestantism, Buddhism, Hinduism and Confucianism.

On Thursday, Francis will meet representatives of all six at Istiqlal mosque, the largest in south-east Asia and a symbol of religious coexistence. It is linked via a “tunnel of friendship” to the cathedral across the road, where Christians in recent days have been taking selfies with a lifesize cutout of the pope.

At the mosque, Pope Francis will sign a joint declaration with the grand imam, Nasaruddin Umar.

The statement will focus on “dehumanisation”, notably the spread of violence and conflict, particularly to women and children, as well as environmental degradation, according to the Indonesian bishops’ conference.

The pope has repeatedly urged the world to do more to combat climate change and mitigate its effects – including rising sea levels, which threaten the heavily polluted megalopolis of Jakarta.

Security is tight for the three-day visit, with the military, police and members of the president’s own detail among more than 4,000 law enforcement officers deployed.

A billboard declaring “Welcome Pope Francis” has been put up in central Jakarta, while the government has ordered a special stamp in his honour.

The country’s religious affairs ministry has hailed the visit as a symbol of Indonesia’s religious diversity.

“It is very important in conveying a message and showing the world that religious harmony in Indonesia is guaranteed and has been implemented,” ministry spokesman Sunanto, who goes by one name, said on Monday, according to state news agency Antara.

It is the third papal visit to Indonesia, an archipelago of 17,500 islands, after Paul VI in 1970 and John Paul II in 1989.

Despite Indonesia’s official recognition of different faiths, there are concerns about growing discrimination, including against Christians, with local Catholics hoping the pope will speak out.

Michel Chambon, a theologian and anthropologist at the National University of Singapore, said the pope would be pressing a wider message he has already delivered in other Muslim-majority countries, from Iraq to Bahrain, Turkey and Morocco.

The visit “is not really aimed at Catholics in Indonesia” but is intended to highlight the global importance of Islamic-Christian dialogue, he told AFP.

Francis will meet the outgoing president, Joko Widodo, during his visit and hold meetings with young people, diplomats and clergy. He will also preside over a mass in an 80,000-seat stadium, one of several such events during the tour, the 45th overseas trip of his papacy.

Originally planned for 2020 but postponed due to the Covid pandemic, the visit takes place three months before his 88th birthday.

The pope has come to routinely use a wheelchair to move around, underwent hernia surgery in 2023 and has been plagued by respiratory issues.

He has not travelled abroad since visiting Marseille in France in September 2023, having cancelled a planned address at UN climate talks in Dubai two months later.

He will be travelling to Indonesia with his personal doctor and two nurses, but Vatican spokesman Matteo Bruni said that was normal and no extra precautions were in place.