Washington (CNN) The White House's personnel director has told President Donald Trump that neither immigration hardliner Ken Cuccinelli nor Customs and Border Protection chief Mark Morgan are eligible to succeed Kevin McAleenan as acting Homeland Security secretary, a senior administration official confirmed to CNN.

The Justice Department's Office of Legal Counsel concluded that neither of the two men, who were said to be Trump's favorites to succeed McAleenan and filling acting posts at the Department of Homeland Security, are eligible to succeed McAleenan because they had not served at least 90 days under the last Senate-confirmed Homeland Security secretary, Kirstjen Nielsen.

The official said Sean Doocey, the White House personnel chief, was the messenger in conveying Justice Department's Office of Legal Counsel's legal opinion to the President.

The administration is yet again seeking someone to fill the top post at the Department of Homeland Security, after a year of high border apprehension numbers and leadership turnover. In April, the White House's growing frustration with leadership led to Nielsen's ouster that placed McAleenan at the helm. Since then, many of the leading roles in the department have been filled with people serving in an acting capacity, leaving few choices within the department to fill the acting secretary post.

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