Former White House chief of staff John Kelly frequently described the Department of Homeland Security as a "mess," a former official said in a Washington Post report.

Kelly, who led the DHS prior to becoming Trump's chief of staff, reportedly complained about the department's state when he was in both roles.

The Department of Homeland Security consists of numerous federal agencies, including the Transportation Security Administration, the Coast Guard, Customs and Border Protection, Secret Service, and Immigration and Customs Enforcement.

White House senior adviser Stephen Miller reportedly told other aides that the DHS had too many agencies and should be streamlined.

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Former White House chief of staff John Kelly frequently described the Department of Homeland Security as a "mess," a former official said in a Washington Post report published Wednesday.

Kelly, who led the DHS prior to becoming Trump's chief of staff, reportedly complained about the department's state when he was in both roles. But efforts to reorganize the department never took off or garnered interest, The Post said.

The Department of Homeland Security consists of numerous federal agencies, including the Transportation Security Administration, the Coast Guard, Customs and Border Protection, Secret Service, and Immigration and Customs Enforcement.

White House senior adviser Stephen Miller told other aides that the DHS had too many agencies and should be streamlined, a former senior official said to The Post. Miller reportedly described the department as a "total problem" that consisted of employees who sought to undermine Trump.

Kelly, a retired four-star Marine Corps general, became the Trump administration's first Homeland Security secretary in January 2017. Kelly previously served as the commander of US Southern Command during President Barack Obama's term and led the United State's military affairs in Central and South America.

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He was later selected to become Trump's White House chief of staff and replaced Reince Priebus in July 2017. Kelly's chief of staff at the DHS, Kirstjen Nielsen, was eventually nominated to replace him.

Kelly's tenure in the White House was marked by numerous reports of disagreements with senior officials, including Trump's son-in-law Jared Kushner and daughter Ivanka Trump. By the time Kelly left, he was reportedly not on speaking terms with the president.

Kelly resigned in late December 2018. Nielsen followed suit earlier this month.