By Evan Perez

WASHINGTON (CBS/CNN) — The acting Attorney General Sally Yates has told Justice Department lawyers not to make legal arguments defending President Donald Trump’s executive order on immigration and refugees, according to sources familiar with the order.

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Yates, an Obama appointee who is serving until Trump attorney general nominee Jeff Sessions is confirmed, does not believe the substance of the order is lawful, according to the sources.

Her order is enforced only until she leaves office.

Currently, there are cases filed in at least five states including Virginia, New York, Massachusetts, Washington and California that are challenging Trump’s order.

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Government officials say at least 348 were denied boarding planes over the weekend.

The White House says it’s working on a 90-day review of the vetting process for immigrants.

Trump’s order bars citizens from Iraq, Syria, Iran, Libya, Somalia, Sudan and Yemen from entering the U.S. for the next 90 days.

The Trump administration says the seven countries that are part of the ban were designated by the previous administration as posing a threat to national security under the current visa program.

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