WASHINGTON, D.C.: The U.S. travel industry is warning that any move to halt the processing of international passengers and cargo at Newark Liberty International Airport could have severe economic consequences, including an estimated US$8 billion annual hit to tourism spending.

The warning came after Homeland Security officials suggested the Trump administration could reassign customs personnel from Newark due to disputes over local authorities' cooperation with immigration enforcement.

The U.S. Travel Association said removing immigration and customs processing at the airport would cause "immediate and lasting harm" to travelers, businesses, and the broader economy.

The group noted that customs officers at Newark process roughly 5 million Americans returning home each year.

"American travelers from across the U.S. could find their flights into the U.S. diverted or canceled," the association said. "Millions of international visitors will face the same disruption, and with the FIFA World Cup weeks away, the damage to America's reputation as a welcoming destination would be significant and lasting."

The organization added that a shutdown could also threaten billions of dollars in imported cargo moving through the airport.

The warning follows comments from Homeland Security Secretary Markwayne Mullin, who said on Thursday that the administration could stop processing international travelers and cargo at Newark because local law enforcement agencies in northern New Jersey were not assisting federal immigration officials.

Mullin complained that local police were not ensuring federal immigration officers could access and leave a detention facility in New Jersey. He warned that customs personnel could be reassigned from Newark Airport if the situation continues.

Earlier in the week, Mullin said the administration was developing plans that could halt the processing of international travelers and cargo at airports located in so-called sanctuary cities that have declined to cooperate with federal immigration enforcement efforts.

Such a move could disrupt international travel and trade at several major U.S. airports, particularly as the country prepares to host large numbers of visitors for the upcoming FIFA World Cup.

The World Cup final is scheduled for July 19 in East Rutherford, New Jersey, approximately 12 miles from Newark Airport.

The U.S. Justice Department recently released a list of sanctuary cities and states that includes several major transportation hubs, such as Boston, Denver, Philadelphia, Chicago, Los Angeles, New York City, Newark, Seattle, and San Francisco.

According to industry figures, more than 50 million international travelers arrived through the three major New York-area airports last year.