FILE - U.S. Immigration and Customs Enforcement (ICE) officers detain a suspect as they conduct a targeted enforcement operation in Los Angeles, Feb. 7, 2017.
FILE - U.S. Immigration and Customs Enforcement (ICE) officers detain a suspect as they conduct a targeted enforcement operation in Los Angeles, Feb. 7, 2017.

U.S. President Donald Trump promised to start deporting "millions of illegal aliens" from the United States next week, but the announced raids on immigrant families appear to have caught the country's immigration officials by surprise.

The deportation plans have been under consideration for months. A Trump administration official says the 1 million migrants who have been issued final deportation orders but are still living in the U.S. would be targeted first. But the most the U.S. has ever deported in a single year was in 2013, when about 435,000 were sent home.

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U.S. immigration officials say despite Trump's announcement, raids on migrant families are not imminent. Reports say the officials were unaware Trump was planning to disclose sensitive law enforcement actions on Twitter.  

Raids on the scale Trump has described could require thousands of law enforcement personnel.  But many immigration agents have already been diverted to the U.S. southern border to control the surge of migrants crossing over from Mexico — more than 140,000 in May alone.

FILE - The U.S. Customs and Border Protection detains migrants who crossed the U.S.-Mexico border in El Paso, Texas, May 29, 2019.

Trump said the country's Immigration and Customs Enforcement agency "will begin the process of removing the millions of illegal aliens who have illicitly found their way into the United States. They will be removed as fast as they come in." 

Boston-based immigration lawyer Matthew Cameron says Trump is making "all kinds of promises that he will never be able to keep" for political purposes that will strike fear in the immigrant community. 

"People are not going to go to their medical appointments," Cameron told VOA. "People are not going to take their kids to school. They're going to skip days in the job, if they really believe there's a possibility. All they hear is, 'We are going to deport a lot of people.' And people who have no reason to be afraid whatsoever will be terrified."

Disclosure unusual

It is unusual for public officials to disclose law enforcement raids in advance, for fear of alerting the targets of the raids, and possibly endangering police and other law enforcement personnel. 

Trump administration officials criticized Oakland, California, Mayor Libby Schaaf last year when she disclosed an imminent immigration raid by warning migrants they could be targeted.

FILE - Oakland Mayor Libby Schaaf speaks at a news conference in Oakland, California, May 13, 2016.

Trump made the immigration raid announcement as he gets ready for the first rally of his official 2020 re-election campaign in Orlando, Florida. He has long made security along the southern border with Mexico and tough enforcement of U.S. immigration laws the hallmark of his presidency.

But Congress has blocked his repeated demands that it approve more than $5 billion in funding for a new border wall. The dispute over Trump's declaration of a national emergency at the border is now tied up in U.S. courts after wall opponents sued to try to block Trump's transfer of money from other projects to pay for it.

Central America migrants

Trump recently threatened Mexico with imposition of a 5% tariff on its exports to the U.S. if it did not step up immigration enforcement to keep migrants from Guatemala, Honduras and El Salvador from reaching the U.S. to seek asylum. But he backed off the tariff threat when Mexico agreed to boost its migration controls at its southern border with Guatemala by sending 6,000 troops to block arriving Central Americans from heading north.

"Mexico, using their strong immigration laws, is doing a very good job of stopping people," Trump tweeted.

But Mexico has refused to become a so-called "safe third country" for people trying to reach the United States. Guatemala on Tuesday contradicted Trump's tweet that it is ready to sign a third country agreement, saying it has not yet agreed to do so.

A nation agreeing to be a "safe third country" would be required to process asylum claims from migrants before they are allowed to move on to their final destination.