Pope Francis expressed his "immense sadness" upon seeing the image of the migrant father and child who drowned in their attempt to cross the Rio Grande, a Vatican spokesman said Wednesday.

"The Pope is profoundly saddened by their deaths, and is praying for them and for all migrants who have lost their lives while seeking to flee war and misery," Holy See Press Office interim director Alessandro Gissoti said June 26.

The graphic image of the bodies of Salvadoran migrant Oscar Alberto Martinez and his 23-month-old daughter, Valeria, floating along the Rio Grande riverbank circulated across the world after they were discovered on June 24.

Martinez and his daughter died while attempting to swim across the Rio Grande along the U.S.-Mexico border after they were unable to make an official request to U.S. authorities for asylum from El Salvador, the Mexican newspaper, La Jornada, reported.

At least 283 migrants died while attempting to cross the U.S.-Mexico border last year, according to U.S. border patrol.

President Donald Trump announced June 22 that he would delay scheduled immigration raids by two-weeks to allow Congress to modify U.S. asylum law.

The House of Representatives passed a bill June 4 that would provide a citizenship path for some brought to the U.S. illegally as children, as well as for qualified holders of Temporary Protected Status or Deferred Enforced Departure.

The bill, the American Dream and Promise Act of 2019, would grant qualifying childhood arrivals 10 years of legal residence, after which they could receive permanent legal residence with two years of higher education or military service, or three years of employment. Those with TPS or DED could apply for lawful permanent residence if they have been in the country for at least three years and have passed background checks. After five years of lawful permanent residence, they would apply for citizenship.

Earlier this month, Mexico agreed to take measures to reduce the number of migrants to the US, in order to avoid the imposition of tariffs.

Some 6,000 National Guard troops will be assigned to Mexico's southern border with Guatemala, and some asylum seekers in the US will be sent to Mexico to wait while their claims are processed.

Pope Francis has been an outspoken advocate for countries to accept migrants and refugees in recent years.

"Before the challenges of contemporary movements of migration, the only reasonable response is one of solidarity and mercy," Pope Francis said at a Mass commemorating migrants who died attempting to cross the Mediterranean Sea from Africa to Europe.

"How many of the poor are trampled on in our day! . . .  Among them, I cannot fail to include the migrants and refugees who continue to knock at the door of nations that enjoy greater prosperity," he said.

Leaders of the U.S. Conference of Catholic Bishops echoed the pope's grief and said the image of the drowned father and daughter demand action.

"This image cries to heaven for justice. This image silences politics. Who can look on this picture and not see the results of the failures of all of us to find a humane and just solution to the immigration crisis?" said Cardinal Daniel DiNardo of Galveston-Houston and Bishop Joe Vasquez of Austin.

DiNardo serves as president of the U.S. bishops' conference, and Vasquez chairs the migration committee.

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"Sadly, this picture shows the daily plight of our brothers and sisters. Not only does their cry reach heaven. It reaches us. And it must now reach our federal government," they said.

The bishops stressed the respect due to every human person, created in the image of God, no matter their legal status or country of origin.

"Recent reports of overcrowded and unsanitary conditions are appalling and unacceptable for any person in U.S. custody, but particularly for children, who are uniquely vulnerable," they said. "Such conditions cannot be used as tools of deterrence. We can and must remain a country that provides refuge for children and families fleeing violence, persecution, and acute poverty."

DiNardo and Vasquez called on Congress to authorize additional spending to meet the needs of children in custody, as well as to raise standards and oversight for facilities on the southern border.

"It is possible and necessary to care for the safety of migrant children and the security of our citizens. By putting aside partisan interests, a nation as great as ours is able to do both," they said.