Work is "both a gift and a duty," Pope Francis told a U.N. labor agency in a message calling for an end to human trafficking and for greater concern for migrants and the unemployed, especially the young.

"At the dawn of creation, God made man the steward of his handiwork and charged him to cultivate and protect it," the Pope said May 28 to the International Labor Conference. "Human labor is part of that creation and continues God's creative work."

Labor is "not a mere commodity" but has "its own inherent dignity and worth."

The International Labor Conference is hosting its 103rd session from May 28-June 12 in Geneva. The conference is sponsored by the International Labor Organization, a U.N. agency that aims to promote internationally recognized labor rights, employment opportunities, social protections and dialogue on work-related issues.

Pope Francis said that Catholic social teaching supports the organization's initiatives that promote "the dignity of the human person and the nobility of human labor."

Citing his 2013 apostolic exhortation Evangelii Gaudium, the Pope said that it is only "through free, creative, participatory and mutually supportive work that human beings express and enhance the dignity of their life."

The pontiff voiced the Holy See's appreciation for the organization's contributions to increasing cooperation between governments, employers and workers.

The Pope noted the problem of unemployment, particularly among the young who can easily become "demoralized" and feel "alienated from society."

"Unemployment is tragically expanding the frontiers of poverty," he said.

Pope Francis also spoke of mass migration as a cause for concern, noting "the sheer numbers of men and women forced to work away from their homelands."

"Despite their hopes for a better future, they frequently encounter mistrust and exclusion, to say nothing of experiencing tragedies and disasters," he said.

Migrant workers can be victims of the "globalization of indifference" and risk the "horror" of human trafficking, forced labor and enslavement.

"This cannot continue! Human trafficking is a scourge, a crime against the whole of humanity," the Pope stressed. "It is time to join forces and work together to free its victims and to eradicate this crime that affects all of us, from individual families to the worldwide community."

He called for a "concerted effort to encourage governments to facilitate the movement of immigrants for the benefit of all" to help eliminate trafficking.

The Pope also called for more cooperation and an expansion of solidarity throughout society.

He spoke of the need for a renewed insistence on human dignity, a "more determined implementation" of global labor standards, better development, and a "re-evaluation" of the responsibilities of international corporations.

The Pope's message concluded with a prayer: "I invoke God's blessing on all that you do to defend and advance the dignity of work for the common good of our human family."

Guy Ryder, director general of the International Labor Organization, delivered his own opening remarks at the conference May 28. He warned of the danger of mistreatment and abuse of migrant workers as well as the problems of forced labor. He spoke of the need to aid transitions from an "informal" economy to a "formal" economy with explicit labor standards.