VATICAN CITY (CNA/EWTN News) - During a press conference Saturday aboard the papal plane from Egypt to Rome, Pope Francis said that in the face of conflict and the possibility of nuclear war, United Nations leaders need to provide a strong leadership, focusing on diplomacy and peaceful negotiation.

"I always say to resolve problems on the path of diplomacy, negotiation."

To find diplomatic solutions to conflict "I believe that the United Nations has the duty to resume their leadership, because it's been watered down a bit," he told journalists April 29.

Asked what he would say to leaders, considering the fear surrounding the possibility of nuclear attack from North Korea, the Pope said that he would call on them to resolve problems "along the path of diplomacy," like he has called on leaders to resolve a variety of problems. 

"The path is the path of negotiation, the path of diplomatic solutions," he said. "This world war in pieces of which I've been talking about for two years, more or less, it's in pieces, but the pieces have gotten bigger, they are concentrated, they are focused on points that are already hot."

"Things are already hot, as the issue of missiles in North Korea has been there for more than a year, now it seems that the thing has gotten too hot."

The issue of nuclear weapons in North Korea has been at the forefront as the UN Security Council met April 28 to discuss how to enforce the several sanctions they have already imposed on North Korea, such as resolution 2321, passed in Nov. 2016, after North Korea's latest successful nuclear test on Sept. 9 of that year.

Hours after their meeting, North Korea filed another missile - early Saturday local time - which exploded within seconds of being launched, American and South Korean defense officials said.

Ahead of the Security Council meeting, U.S. President Donald Trump said that if diplomatic efforts fail, the U.S. is willing to engage with North Korea directly over ending its nuclear weapons program.

Direct conflict is possible, though "he would love to solve things diplomatically," he said in an interview with Reuters April 28. 

The question concerning the threat of a nuclear attack from North Korea was asked during the flight back to Rome after the Pope's April 28-29 trip to Cairo, Egypt.

During the 32-minute long press conference, the Pope also addressed peace in the Middle East and the situation in Venezuela. He also responded to a question about populism, highlighting in particular the difference between populism in Europe and populism in Latin America.

Asked about a possible meeting with Donald Trump, he said that he had not been informed of any request, but that he always meets with heads of state if they ask.

During the brief trip, the Pope made his way to Egypt's prestigious al-Azhar University and adjunct mosque, considered one of the highest authorities in Sunni Islam, where he met with Grand Imam Ahmed el-Tayyeb and addressed participants in the International Peace Conference.

He then met with the country's authorities, including President Abdel Fattah el-Sisi, before heading to the Coptic Orthodox Cathedral for his meeting with Tawadros, the last official appointment of the day.

Saturday he celebrated Mass for around 15,000 people in Cairo's Air Defense Stadium before meeting with local bishops, followed by a prayer meeting with priests, religious and seminarians before he boarded the plane to return to Rome.