The drowning deaths of two migrants is causing a stoush at the highest levels of US politics.
WARNING: GRAPHIC CONTENT
President Donald Trump has blamed his rival Democratic Party for the deaths of two migrants on the US-Mexico border, which were captured in a "heartbreaking" photo earlier this week.
The photo shows the lifeless bodies of El Salvador migrants Oscar Alberto Martinez Ramirez and his 23-month-old daughter Valeria, who drowned while trying to cross the Rio Grande from Mexico into Texas.
"I hate it," Mr Trump told reporters when asked about the image on Wednesday.
"And I know it could stop immediately if the Democrats change the law. They have to change the laws. And then that father, who probably was this wonderful guy, with his daughter, things like that wouldn't happen."
It comes as the US Senate on Wednesday approved a US$4.6 billion bill to address the migrant surge at the border with Mexico, setting up a negotiation with the House of Representatives and Mr Trump over the funds and how they should be spent.
Congressional leaders have a choice between a bill from the Republican-controlled Senate and a more restrictive US$4.5 billion bill passed by the Democratic-led House on Tuesday night. They could also strike a compromise and send that to Trump.
More details emerge
More details emerged on Wednesday about the story of the El Salvador migrant family, who were reportedly unable to request asylum from US authorities.
Mr Martinez's widow, 21-year-old Tania Vanessa Avalos, watched her husband and daughter drown as she waited helplessly on the bank of the Rio Grande river, which separates Matamoros from the city of Brownsville in Texas.
She was also due to fly back to El Salvador later on Wednesday, with a cousin who was travelling with them.
"She's in a state of shock. She's very young for that much suffering. Her nerves are on edge. It's understandable," the head of the Tamaulipas state migration authority, Enrique Maciel, told AFP.
Julia Le Duc, the photographer who took the image, wrote in the Guardian on Wednesday that "these are desperate families – and desperate people do desperate things".
"They'd been in Tapachula in the south of Mexico and they'd applied for a humanitarian visa (allowing them to stay and work in Mexico for a year) but they wanted the American dream – so they took a bus up to the border."
They wanted the American dream
Julia Le Duc
"Will it change anything? It should. These families have nothing, and they are risking everything for a better life."
While Mr Martinez's mother, Rosa Ramirez, said she urged her son not to leave, fearing danger would meet him on the long journey north.
"Ever since he first told me that they wanted to go, I told him not to," Ms Ramirez told Reuters, recalling conversations with her son.
"I had a feeling, it was such an ugly premonition. As a mother, I sensed that something could happen."
Pope Francis was one of many international figures who offered condolences on Wednesday.
"With immense sadness, the Holy Father has seen the images of the father and his baby daughter who drowned in the Rio Grande River," Vatican spokesman Alessandro Gisotti said.
UN High Commissioner for Refugees Filippo Grandi said the family had risked their lives because they could not get the protection they were entitled to under international law.
"The deaths of Oscar and Valeria represent a failure to address the violence and desperation pushing people to take journeys of danger for the prospect of a life in safety and dignity," he said in the statement.
Several 2020 Democratic presidential contenders placed the blame squarely on Mr Trump.
Former congressman Beto O'Rourke tweeted that the president was "responsible for these deaths".
Fellow 2020 hopeful Kamala Harris said "these families seeking asylum are often fleeing extreme violence. And what happens when they arrive? Trump says, 'Go back to where you came from.'
"That is inhumane. Children are dying. This is a stain on our moral conscience."
And New Jersey senator Corey Booker said "these are the consequences of Donald Trump's inhumane and immoral immigration policy. This is being done in our name".
While some have directed criticism at Mexican President Andres Manuel Lopez Obrador.
Mr Lopez Obrador, an anti-establishment leftist, came to power in December vowing to safeguard migrants' rights.
But under pressure from Mr Trump, who threatened to impose tariffs on Mexico, he agreed this month to crack down on undocumented Central Americans trekking toward the US.
"What is happening in this country is unacceptable. We are treating [migrants] like human meat, because of pressure from the great power [the US]," said the speaker of the lower house of Congress, Porfirio Munoz Ledo, a leading figure in Lopez Obrador's party, Morena.
The president responded that he has a "clear conscience."
To manage asylum flows, the US has in recent years implemented a system known as "metering" which puts daily limits on the number of asylum seekers processed at ports of entry, leading to weeks-long waiting lists in dangerous border towns.
That system has contributed to growing numbers of migrants crossing the border illegally to hand themselves in to authorities and ask for asylum.
US officials told Congress on Wednesday they did not have adequate staffing and facilities to adequately handle the surge of migrants seeking asylum at ports of entry.
US border patrol agents have apprehended 664,000 people along the southern border so far this year, a 144 per cent increase from last year, said Brian Hastings, chief of law enforcement operations for the US Border Patrol.
Additional reporting: Reuters, AFP