In a speech to political authorities in the country, which is home to hundreds of tribal groups and more than 800 spoken languages, the 87-year-old Catholic pontiff also made a heartfelt appeal for an end to a spate of ethnic violence that has killed dozens in recent months.

The pope, visiting as part of an ambitious 12-day trip to four countries, said PNG's natural resources were "destined by God" for the whole community.

"Even if outside experts and large international companies must be involved in the harnessing of these resources, it is only right that the needs of local people are given due consideration when distributing the proceeds and employing workers, in order to improve their living conditions," said Francis.

The pope said natural resources should be developed in a sustainable manner that "improves the wellbeing of all, excluding nobody, through [...] international cooperation, mutual respect and agreements beneficial to all parties".

Arriving for his speech at the APEC Haus, a conference centre built for the 2018 Asia-Pacific Economic Cooperation forum, Francis was greeted with a dance from a group of Papua New Guineans wearing traditional outfits featuring feathered headdresses and beaded skirts.

The pope, who uses a wheelchair due to knee and back pain, was rolled past an entry foyer with a curved timber screen inspired by a typical lakatoi tattoo design.

Pope Francis (second left, on wheelchair) greets indigenous people on the day of a meeting with authorities, civil society and the diplomatic corps at APEC Haus in Port Moresby, Papua New Guinea on Sept. 7, 2024. (Reuters/Guglielmo Mangiapane)

In a speech welcoming Francis, PNG Governor-General Bob Dadae thanked the pope for his humanitarian advocacy and called the Catholic Church one of the country's "key development partners".

PNG contains some of the largest known gold deposits and is a major exporter of natural gas and oil. The government, led by Prime Minister James Marape since 2019, has sought to boost local benefits from projects undertaken by international conglomerates such as Exxon Mobil Corp XOM.N and Newcrest Mining.

An economic update in May said that growth in the country was a modest 2.7 percent last year. The World Bank has said it is suffering a "human capital crisis," with nearly half of children showing stunted growth.

Home to hundreds of tribes, PNG has a long history of ethnic warfare. Violent attacks in three remote villages in July likely killed at least 26, according to the United Nations.

Francis on Saturday said it was his "particular hope that tribal violence will come to an end". He said he was appealing "to everyone's sense of responsibility to stop the spiral of violence and instead resolutely embark on the path that leads to fruitful cooperation".

He called for a "definitive solution" to the status of Bougainville Island, the largest island in the Solomon Islands archipelago. Currently an autonomous region of PNG, the island voted overwhelmingly for independence in 2019. But years of political deadlock in PNG's parliament have stalled the vote's ratification.

A sprawling country of mountains, jungle and rivers, PNG has a population estimated at anywhere from 9 million to 17 million. The Vatican estimates there are around 2.5 million Catholics in the country.

Francis landed in PNG on Friday evening, after a trip to Indonesia, and will stay until Monday. He will then visit East Timor and Singapore before heading back to Rome on Sept. 13. It is his longest overseas trip yet.

Although Francis' speech on Saturday touched on serious issues, the pope also showed some of his trademark humour. Noting the number of languages spoken across PNG, he said the diversity of expression fascinated him.

"I imagine that this enormous variety is a challenge to the Holy Spirit, who creates harmony amid differences!" the pope said.