The theme chosen by Pope Francis for World Day of Migrants and Refugees 2017 will reflect on "vulnerable and voiceless" minors, the Vatican announced June 22. 

The Pope also will release a message for the world day prior to its celebration, which will be Jan. 15 in most countries.

Explaining the Pope's choice for the theme, the Pontifical Council for Migrants and Travellers said the Pope wants "to focus attention on the littlest of the little."

"Oftentimes, children arrive alone in their countries of destination, they are unable to make their voices heard and easily become victims of grave violations of human rights," the council's statement said.

The World Day of Migrants and Refugees began in 1915 "to raise awareness on the phenomenon of migration and promote a collection to support pastoral work" for Italians emigrating to other countries and the formation of missionaries to assist them, the council said.

Today, however, "migration is a global phenomenon, not just European or Mediterranean," the council's statement said. "All continents are touched by this reality that does not exclusively affect people looking for work or better living conditions, but also adults and minors who are fleeing true tragedies."

All nations, but especially those receiving migrants, must ensure that all refugees "enjoy full recognition of their rights."

"Children and women represent the most vulnerable category within this great phenomenon and minors are particularly the most fragile, often invisible because they are undocumented or unaccompanied," the council's statement said.