A Honduran migrant protects his child after fellow migrants, part of a caravan trying to reach the U.S., stormed a border checkpoint in Guatemala, in Ciudad Hidalgo, Mexico October 19, 2018. REUTERS/Ueslei Marcelino TPX 

REUTERS/Ueslei Marcelino TPX 

U.S. President Donald Trump's administration on Monday cut hundreds of millions of dollars in aid to El Salvador, Guatemala and Honduras, after Trump blasted the three countries because thousands of their citizens had sought asylum at the U.S. border with Mexico.

The plan will likely encounter stiff opposition in Congress.

Lawmakers, including some of Trump's fellow Republicans as well as Democrats, have chafed against the president's repeated decisions to disregard spending bills passed by Congress, some of which he has signed into law himself.

Lawmakers who opposed the plan said it was cruel to cut off aid to countries grappling with hunger and crime and that the move would be counterproductive because it would more likely increase the number of migrants than decrease it.

Congressional aides said the administration told them it would reallocate $370 million in aid to Central America that lawmakers had approved for fiscal 2018, and suspend an additional $180 million Congress had approved for fiscal 2017.

All of the money for those years has not yet been spent. According to a transcript of a press briefing with State Department spokeswoman Morgan Ortagus reviewed by CNBC, the grants and contracts already awarded will continue with current funding.

The administration said in March it would cut aid to the three countries after Trump expressed unhappiness with the their immigration policies.

No funds will be provided until the administration is satisfied the countries are reducing the number of migrants reaching the U.S. border, State Department spokeswoman Morgan Ortagus told reporters.

"This is consistent with the president's direction and with the recognition that it is critical that there be sufficient political will in these countries to address the problem at its source," she said.

Without elaborating, she added: "Working with Congress, we will reprogram those funds to other priorities as appropriate."

A U.S. official, with knowledge of plans, said the administration would review the funding by April 2020.

—CNBC's Kevin Breuninger and Jesse Pound contributed to this report.

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