As part of extreme methods to deter migrants from crossing the southern border, U.S. President Donald Trump recently suggested shooting migrants in the legs to slow them down, a new book has said.

The book, by two New York Times journalists, said Trump also wanted his new border wall to be electrified “with spikes on top that could pierce human flesh”.

He further wanted a snake or alligator-infested moat, according to an excerpt of the book called “Border Wars: Inside Trump’s Assault on Immigration.”

Michael Shear and Julie Hirschfeld Davis, the Times reporters and authors of the book, said Trump made these suggestions in March during a meeting where he also asked for the entire border with Mexico to be closed.

That week, the president had allegedly become frustrated since his moves to stop illegal immigration seemed not to be yielding results.

Thus, he threatened to close the U.S.-Mexico border but during the March meeting, his advisers talked him out of it, according to the Times reporters.

The claims in the book, based on interviews with scores of officials within the White House and the administration, are not at variance with the president’s public posture towards immigration.

Last year, he publicly suggested that soldiers shoot migrants who throw rocks at them.

Even though he didn’t go ahead with this suggestion, the Times reporters said he fired aides and advisers who were against his ideas, including homeland security secretary Kirstjen Nielsen.

Trump has, so far, dismissed the claims in the report, tweeting: “Now the press is trying to sell the fact that I wanted a Moat stuffed with alligators and snakes, with an electrified fence and sharp spikes on top, at our Southern Border. I may be tough on Border Security, but not that tough. The press has gone Crazy. Fake News!

Since his 2016 campaign, Trump has made a crackdown on illegal migration a key priority of his presidency.

In July, the administration announced that any migrant who cannot prove that they have been in the United States continuously for more than two years will be immediately deported without a hearing before a judge.

Critics believe that the rule could prevent asylum seekers from applying for refuge in the U.S. before they are deported. 

Last September, it was announced that Trump wants immigrants to pay more to appeal their deportations, proposing $1000 fee in place of current $110.

Experts say this is another tactic the anti-immigration Trump administration is employing to tighten the means by which immigrants get legal status.

In the latest development, the Trump administration has issued a proclamation that will bar immigrant visa applicants from entering the U.S. unless they can prove they will have health insurance or the means to pay for medical care, the CNN reports.

Visa immigrants must be covered by health insurance within 30 days of entering or have enough financial resources to pay for any medical costs. The measure will be effective November 3.

The new rule applies to people seeking immigrant visas from abroad – not those already in the U.S. It will also not affect lawful permanent residents and does not apply to asylum seekers, refugees or children.  

It would, however, apply to the spouses and parents of U.S. citizens and this could affect families who want to bring their parents to the U.S.