(Bloomberg Government) -- Chris Magnus, the Biden administration’s top border official, has been asked to leave but has refused to step down, according to a person familiar with the matter.

Department of Homeland Security Secretary Alejandro Mayorkas told Magnus to resign or be fired by President Joe Biden, the person said.

Magnus, the former police chief in Tucson, Ariz., has led US Customs and Border Protection since last year and has faced criticism for continued high numbers of migrant encounters at the US-Mexico border and complaints from some colleagues that he’s not fully engaged in his work.

House Republicans, who’ve taken aim at the Biden administration’s border policies, called on Magnus to resign earlier this month, citing a Politico report that he was skipping high-level meetings on border security.

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DHS officials and congressional committees with oversight over the border didn’t immediately respond to requests for comment. The White House declined to comment.

Magnus defended his performance in a recent interview with Bloomberg, saying his critics were reacting to his efforts to improve morale, accountability, and transparency within CBP.

The Los Angeles Times and Politico first reported the news of the resignation request.

To contact the reporters on this story: Jordan Fabian in Washington at jfabian6@bloomberg.net; Ellen M. Gilmer in Washington at egilmer@bloombergindustry.com

To contact the editors responsible for this story: Bennett Roth at broth@bgov.com; Angela Greiling Keane at agreilingkeane@bloombergindustry.com

(Updates with additional information throughout.)

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