President Donald Trump confirmed on Saturday that he is considering a new family separation policy at the US-Mexico border because he believes the administration's earlier move to separate migrant children from parents was an effective deterrent to illegal crossings.

Asked to respond to a report in The Washington Post that the administration is weighing a new family-separation policy, Mr Trump told reporters, "We're looking at everything that you could look at when it comes to illegal immigration."

Mr Trump said the soaring number of illegal border crossings is "a terrible situation" and argued that family separations likely would help scare away some undocumented migrants from trying to enter the United States.

"If they feel there will be separation, they won't come," Mr Trump said.

Mr Trump made his comments to reporters on the South Lawn of the White House before boarding Marine One for his trip to Kentucky, where he was scheduled to headline an evening campaign rally.

Mr Trump attributed the rise in illegal border crossings to the robust economy.

"We have people that are trying to get into our country because of how well our country is doing," Mr Trump said. "You know, in the old days, when the country wasn't doing well, it was a lot easier. Now everybody wants to come in, and they come in illegally, and they use children. In many cases, the children aren't theirs. They grab them, and they want to come in with the children."

Undocumented immigration across the US-Mexico border Show all 14 1 /14 Undocumented immigration across the US-Mexico border Undocumented immigration across the US-Mexico border Immigrant children, many of whom are separated form their parents, are housed in Texas' tent city Reuters Undocumented immigration across the US-Mexico border A two-year-old Honduran asylum seeker cries as her mother is searched and detained near the US-Mexico border Getty Undocumented immigration across the US-Mexico border Undocumented migrants ride on the top of a freight train referred to as the beast, or La Bestia Getty Undocumented immigration across the US-Mexico border A cage inside a US Customs and Border Protection detention facility in Texas Reuters Undocumented immigration across the US-Mexico border US Border Patrol Academy All new agents must complete a months-long training course at the New Mexico facility before assuming their posts at Border Patrol stations, mostly along the US-Mexico border Getty Undocumented immigration across the US-Mexico border US-Mexico border fence A group of young men walk along the Mexican side of the US-Mexico border fence in a remote area of the Sonoran Desert Getty Undocumented immigration across the US-Mexico border US-Mexico border fence in the US Man looks through US-Mexico border fence into the US in Tijuana, Mexico Getty Undocumented immigration across the US-Mexico border US-Mexico border fence US Border Patrol agent Sal De Leon stands near a section of the US-Mexico border fence while stopping on patrol on in La Joya, Texas Getty Undocumented immigration across the US-Mexico border US Border Patrol Academy US Border Patrol instructor yells at trainees after their initial arrival to the academy Getty Undocumented immigration across the US-Mexico border Memorial service in Guatemala Families attend a memorial service for two boys who were kidnapped and killed in San Juan Sacatepequez, Guatemala. Crime drives emigration from Guatemala to the United States, as families seek refuge from the danger Getty Undocumented immigration across the US-Mexico border Arrests on the border Undocumented immigrants comfort each other after being caught by Border Patrol agents near the US-Mexico border Getty Undocumented immigration across the US-Mexico border Detention holding facility A boy from Honduras watches a movie at a detention facility run by the US Border Patrol Getty Undocumented immigration across the US-Mexico border Mexican farm workers Mexican migrant workers harvest organic parsley at Grant Family Farms in Wellington, Colorado Getty Undocumented immigration across the US-Mexico border Mexican family in Arizona A Mexican immigrant family sits in the living room of their rented home in Tuscon, Arizona. The family that Arizona's new tough immigrant law had created a climate of fear in the immigrant community. Getty

The president later added: "You have really bad people coming in and using people. They're not their children. They don't even know the children. They haven't known the children for 20 minutes. And they grab children and they use them to come into our country."

In August the country saw a 38 per cent increase in the number of migrants arrested and charged with illegally crossing the border, Department of Homeland Security officials said.

The Post first reported on Friday that the White House was actively considering plans to again separate parents and children at the US-Mexico border. Senior administration officials noted, however, that they are not planning to revive the chaotic forced separations carried out by the Trump administration in May and June that spawned an enormous political backlash and led to a court order to reunite families.

One option under consideration, according to the report, is for the government to detain asylum-seeking families together for up to 20 days, then give parents a choice: Stay in family detention with their child for months or years as their immigration case proceeds, or allow children to be taken to a government shelter so other relatives or guardians can seek custody.