Washington (CNN) The head of a union representing US Citizenship and Immigration Services employees on Sunday slammed Ken Cuccinelli, an immigration hardliner who President Donald Trump is expected to tap to lead the agency, saying his potential appointment "spells the end of legal immigration as it currently exists."

"The resignation of Francis Lee Cissna as Director of USCIS and the possible appointment of Ken Cuccinelli as his successor spells the end of legal immigration as it currently exists," Danielle Spooner, the president of the union representing all USCIS employees, said in a statement.

"It has become clear that the goal of this Administration is to end immigration all together. How better to do that then by appointing as the leader of USCIS someone who knows nothing about immigration, Adjustment of Status or Naturalization, and whose sole purpose is to destroy the agency that grants these benefits," the statement read.

Cuccinelli did not immediately respond to CNN's request for comment Monday.

The rebuke comes several days after L. Francis Cissna, the agency's current head, announced he would be stepping down amid a major shakeup in the last month among the leadership at the Department of Homeland Security.

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