Pope Francis urged leaders in Luxembourg, a small but prosperous nation with the highest density of millionaires per capita globally, to allocate resources to enhance conditions in developing countries during a visit on Thursday.

The 87-year-old pontiff, who was in the landlocked state for a day, suggested that boosting foreign aid could help curb the influx of refugees and migrants into Europe. "Let us not forget that wealth carries responsibility," Francis told a gathering of political and civil leaders at Luxembourg's Cercle Cite, a neo-baroque palace. "I call for continuous vigilance so that the most disadvantaged nations may be assisted in rising from their impoverished conditions."

This is a rare European visit for Francis, who will also travel to Belgium later in the day. He typically visits places never before visited by a pope or where Catholics are a minority. The pope, who has prioritized care for migrants during his 11-year papacy, praised Luxembourg for setting "an example in guiding the way forward in welcoming and integrating migrants and refugees." Nearly half of Luxembourg's 654,000-strong population are foreign nationals, mainly from neighboring countries like France, Belgium, and Germany.

In an impromptu remark, the pope addressed Luxembourg's low fertility rate, saying, "Please, more children." Referencing past jokes about Western countries having more pets than kids, he promised not to repeat them but reiterated, "More children." Luxembourg Prime Minister Luc Frieden, in his welcome speech for Francis, highlighted that the Luxembourg constitution proclaims human dignity as a "fundamental right." "We must each of us continually strive to ensure that this dignity is upheld," he said.

Later Thursday, Francis met with local Catholics at an event in Luxembourg's Notre-Dame Cathedral. Hundreds of people gathered outside the 17th-century church to greet the pope, many holding umbrellas under overcast, drizzling skies. In Belgium, where the pope is scheduled to travel later Thursday, he will hold a private meeting with 15 survivors of clergy abuse, according to the country's ambassador to the Vatican, Patrick Renault. Over 700 complaints and reports of abuse involving the church have been filed in Belgium since 2012, according to a church report. In March, the pope expelled a former Belgian bishop from the priesthood after he admitted to sexually abusing two nephews.

On his flight from Rome on Thursday morning, Francis briefly greeted the journalists accompanying him on the plane but did not tour the aircraft to meet them individually, as he usually does. The pope, who now uses a wheelchair due to knee and back pain, said he did not feel up to "making the trip" around the back of the single-aisle aircraft. According to the Vatican, Luxembourg, a country covering an area of 2,586 square kilometers, has about 271,000 Catholics among its population.