WASHINGTON, United States (AFP) — The White House on Sunday defended President Donald Trump’s decision to cut off aid to three small Central American countries, insisting they weren’t doing enough to stop the flow of migrants to the United States.

Trump announced the aid cut-off to El Salvador, Honduras and Guatemala last week and threatened once again to close the US border with Mexico in response to the migrant surge.

“If we’re going to give these countries hundreds of millions of dollars, we would like them to do more,” White House chief of staff Mick Mulvaney said on CNN’s “State of the Union.”

The aid has gone to fund programs to combat gangs and foster development in the three countries, with the aim of addressing the root causes of the mass migration.

“If it’s working so well, why are the people still coming?  Why are these historic numbers — again, 100,000 people will cross the border this month alone,” Mulvaney said.

“It’s not working well enough to help us solve our border crisis.  And that’s what the president’s focused on,” he said.

Critics warned, however, that US funding cuts are likely to worsen conditions, possibly adding to the migrant flow. And they said Trump’s  threat to close the border with Mexico, if carried out, would hurt the US economy.

Senator Dick Durbin, a Democrat from Illinois, dismissed the threat to close the border as “a totally unrealistic boast” by Trump.

“We need to focus on what’s happening in Central America where three countries are disassembling before our eyes and people are desperately coming to the United States. The president cutting off aid to these countries will not solve this problem,” he said on NBC’s “Meet the Press.”

White House counselor Kellyanne Conway, speaking on “Fox News Sunday,” insisted Trump’s threat to close the border “certainly isn’t a bluff.”

On Saturday, Secretary of State Mike Pompeo announced that, at the president’s direction, the State Department was ending its foreign assistance programs for the three Central American countries for 2017 and 2018.

The State Department did not say how much unspent money was involved in the step, which could be largely symbolic.

In comments to reporters Friday, Trump suggested as much as US$500 million is at stake.

“We were giving them US$500 million. We were paying them tremendous amounts of money, and we’re not paying them anymore because they haven’t done a thing.”

In response to the aid cuts, Honduras proposed Sunday that it, Guatemala and El Salvador consider undertaking joint initiatives “to ensure the sovereignty and dignity of each nation” in light of “the contradictory policies of the United States.”