Pope Francis began his visit to Panama on Thursday with a call to political leaders to reject “all forms of corruption” in a speech to the diplomatic community.

Francis, in Panama for a global gathering of young Catholics, said those in positions of authority should “lead a life that demonstrates that public service is a synonym of honesty and justice, and opposed to all forms of corruption.”

In a speech delivered to government ministers and diplomats at the foreign ministry, He said young people demanded a greater commitment from politicians.

“They call upon them to live in simplicity and transparency, with a clear sense of responsibility for others and for our world.”

Young people demanded a commitment to “a politics that works to build a culture of greater transparency,” Francis said.

Francis was speaking at the beginning of a visit in which he will celebrate two open-air masses for around 200,000 young pilgrims from around the world gathered in Panama for World Youth Day celebrations.

He was to formally open the jamboree at a prayer meeting later Thursday.