Pope Francis says migrant children in the United States need to be welcomed and protected, as churches from many traditions face up to the impact of population movement.

"A change of attitude towards migrants and refugees is needed on the part of everyone," said Francis in a July 14 letter to the Mexico/Holy See Colloquium on Migration and Development.

He said the numbers of children undertaking hazardous journeys "are increasing day by day," the Vatican press service said.

"Many people forced to emigrate suffer and, often, die tragically; many of their rights are violated, they are obliged to separate from their families and, unfortunately, continue to be the subject of racist and xenophobic attitudes," said the Pope.

The pontiff called for "the international community to pay attention to this challenge" and for measures to be taken by the countries involved.

These include policies to inform the public of the dangers of the trip north and to promote development of the migrants' countries of origin.

And since these people escape their countries because of extreme poverty, development measures should be prioritized in the countries where these migrants originate.

Frances noted that migration poses a big challenge to the international community.

JOURNEY NORTH DANGEROUS

The journey to the north is dangerous, especially for children.

A six-year-old girl from Honduras described to CNN the hazardous trek in vivid detail: Stowing away on freight trains; walking through a forest at night; encountering monkeys and snakes.

Despite the danger, the mother of the girl said that they'll probably make the trek again because they have nothing left in Honduras.

Last week, the National Hispanic Christian Leadership Conference (NHCLC) began a campaign to work with Latin American churches to warn parents not to send their children to the United States, CBN reports.

NHCLC represents more than 40,000 Hispanic evangelical churches in the United States and 500,000 worldwide.

Rev. Samuel Rodriguez, president of NHCLC/Conela, warned that unaccompanied children in the United States could fall victim to the same drug gangs that threaten them in Central America.

Other Christian groups are also willing to help by providing spiritual encouragement to the hundreds of illegal immigrant children.

But the pastors in Arizona and Texas revealed that they have been denied access to immigration camps, Fox News reported last July 9.

"Border Patrol told us pastors and churches are not allowed to visit," said Kyle Coffin, the pastor of CrossRoads Church in Tucson, Arizona.

"It's pretty heartbreaking that they don't let anybody in there - even credentialed pastors."

The Border Patrol told Fox News in a statement, "Due to the unique operational and security challenges of the Nogales Placement Center, religious services provided by outside faith leaders are not possible at this time."

Pastor Chad Mason of Calvary Baptist Church told CBN it is heartbreaking to know there's a need but they have no access to try and care for that need.

He said that the Border Patrol is not designed to be a childcare facility as its members are police officers.

U.S. Border Patrol agents have already detained more than 50,000 children as young as six-years-old.