Censor.NET reports citing BBC.
Building a 2,000-mile barrier along the Mexican border was one of Trump's key pledges in the election campaign.
He said in a TV interview that Mexico would "absolutely, 100%" reimburse the U.S. for his wall.
"There will be a payment. It will be in a form, perhaps a complicated form," he said, adding Mexico would finally benefit from the wall.
The Mexican authorities have repeatedly said they won't finance the project either at the time of building or in the future. Last year, President Enrique Pena Nieto pointed out that the number of illegal immigrants from Mexico to the United States decreased significantly since it had peaked 10 years before.
Trump also signed an action to strip funds from U.S. cities that are sanctuaries for undocumented immigrants.
Trump's order to block federal grants could cost these cities millions of dollars. But the administration may face legal challenges, given that some federal courts have backed cities that say they cannot hold immigrants beyond their jail term at the say-so of federal authorities.
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