Pope Leo XIV issued a call for peace and dialogue at the outset of his trip to Spain on Saturday.
Meeting representatives of the state, civil society and foreign diplomats in Madrid, the pope lamented the fact that "the message of peace, in these times, unfortunately sounds naïve to some and provocative to others."
His words may be understood by some as reference to a spat in May when US President Donald Trump responded with fury to the pontiff's criticism of the war on Iran.
Pope Leo thanked Spain – whose left-wing government has also drawn Trump's ire – for its "commitment to international law and multilateralism".
Instead of "divisive and polarizing" remarks about the world, he said, we must move from "fruitless simplifications to a fruitful recognition of its complexity."
Leo was welcomed by King Felipe VI and Queen Letizia at the start of his six-day visit.
On Saturday evening, the pope is due to hold a celebration with young people from across Spain is planned for the evening in Madrid's Plaza de Lima.
Upwards of 100,000 people are expected to attend the prayer vigil, during which the faithful will pray psalms, hold biblical readings and read other spiritual texts together.
Young people will also be able to ask the pope questions during the event, according to the organizers for the trip, acting on behalf of the Archdiocese of Madrid and the Spanish Bishops' Conference.
Even before landing in Spain, the pope was calling for peace. As he flew to Madrid, he once again called for an end to Moscow's war on Ukraine.
"We really must press for an end to the violence," Leo said, according to the Italian news agency ANSA. "The situation is getting worse and worse. Four and a half years have already passed. A solution must be found."
Hundreds of thousands of people are expected to attend the scheduled open-air events throughout the papal tour, carried out under the banner, "Lift up your eyes."
Further highlights include the blessing of the Jesus Tower at the Sagrada Família basilica in Barcelona on Wednesday – the 100th anniversary of the death of architect Antoni Gaudí – and two meetings in the Canary Islands with migrants from Africa.
The Vatican has also announced that the pope will meet with victims of sexual abuse in Catholic institutions, in line with calls by victims' associations. Leo described the abuse scandals on the flight as remaining an "open wound" for the Catholic Church.
This is the first visit to a major European country outside Italy for the US-born pontiff, who has been at the helm of the Catholic Church since May last year.
Before his election as head of the world's 1.4 billion Catholics, Leo spent more than a quarter of a century in Peru as a missionary and bishop, and he speaks excellent Spanish.
The Catholic Church in Spain hopes that the visit will encourage more people to return to the faith. While in the 1970s almost 100% of Spaniards identified as Catholic, the figure today stands at just over half.
