Democratic presidential candidate Joe Biden has vowed to reverse several immigration policies implemented by President Donald Trump's administration.

However, the Trump administration claimed that there would be illegal crossings surge at the southern border should Biden deliver his promise.

The administration officials said they are seeing it happening now, according to a Fox News report.

Biden has promised to end the administration's immigration policies that are key to ending "catch-and-release," a procedure wherein migrants are released into the U.S. while waiting for immigration trials. 

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Ending catch-and-release discourage migrants who headed north whether they had a valid asylum claim or not. That is because they could be released into the country, according to a Fox News report.

Another immigration policy was the Migrant Protection Protocols (MPP), also known as the "Remain in Mexico" policy. This policy sent migrants to Mexico to wait for hearings.

Over 60,000 migrants were enrolled in the protection protocols. Many of those were waiting south of the border, miles away from towns like Laredo, Texas. Immigrant courts are set up in Laredo, Texas. Not many are allowed into the country.

Democrats and immigration activists said this immigration policy is cruel, adding that it forces migrants to wait at dangerous camps in Mexico.

Immigrants staying in these camps can suffer violence at the hands of cartels and criminals. Biden promised to end this policy when he enters the White House. 

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Many claimed that this could cause illegal crossings to surge at the border, with tens and thousands of migrants already entering. This could be followed by thousands more from Northern Triangle countries such as Honduras, Guatemala, and El Salvador.

Acting Customs and Border Commissioner Mark Morgan told Fox News that it would be a disaster if protection protocols ended.Morgan was appointed by Trump. He was also the head of the U.S. Border Patrol during the Obama administration.

Morgan noted that in the 2019 fiscal year, Customs and Border Protection (CBP) and Immigration and Customs Enforcement (ICE) released more than 500,000 into the United States. He said that if the MPP is to go away, it will be "absolutely devastating."

Morgan said the policy is an "integral part of the network of policies that allowed us to end catch-and-release."

Morgan earlier said that in October, CBP faced 69,000 immigrants entering the country without legal permission. He said this is an increase of 21 percent from September and a 54 percent increase from October 2019.

Morgan further warned that removing MPP and other policies that critics wanted to remove will sound the alarm "that our borders are open."

Acting Homeland Security Secretary Chad Wolf also cautioned against reversing Trump's immigration policies, saying if these policies were removed, people would be imperiled by another immigration crisis.

However, Biden intends to "build security and prosperity" in Central America. The former president believes that this will solve the root causes of "irregular migration."

He also vowed to end the Asylum Cooperative Agreements with Northern Triangle countries and impose a 100-day moratorium on deportations.

Biden said he would also urge Congress to pass a "path to citizenship" for immigrants living in the U.S. without legal permission.