President Trump officially announced his nominee to head the Department of Homeland Security Thursday, introducing Kirstjen Nielsen, most recently a White House aide dubbed Chief of Staff John Kelly's enforcer.
'Kirstjen plays a crucial role in managing White House functions and coordinating with federal agencies and with Melania, who has got – really, she's done some great work for a lot of different groups,' Trump said at a ceremony in the East Room.
'And she is the one that will very much miss you in your current position, I can tell you,' the president continued.
He looked for his wife in the crowd. 'Is that a correct statement?' he asked. 'She was a little disappointed to hear this news,' Trump said to laughs.
Nielsen who worked under Kelly at DHS before coming to the White House – only to go back to DHS in Kelly's old role – has earned a reputation of being tough to work with, as Kelly worked to narrow the flow of information and people into the Oval Office.
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Kirstjen Nielsen, President Donald Trump's nominee to be the next secretary of Homeland Security, speaks during an event in the East Room of the White House on Thursday
President Donald Trump congratulates Kirstjen Nielsen, his nominee to be secretary of Homeland Security, in the East Room
First lady Melania Trump attended an East Room ceremony at the White House Thursday announcing her husband's new DHS pick
First lady Melania Trump (left) greets Secretary of State Rex Tillerson (right) at President Trump's announcement that he's chosen Kirstjen Nielsen to be DHS head
First lady Melania Trump is photographed entering a ceremony for President Trump's nominee for DHS head Kirstjen Nielsen, who the president said the first lady would miss, as Nielsen's been working at the White House for the past couple months
That has included limiting access to the president to some who had formerly enjoyed near-unimpeded access.
On Thursday, however, Trump called attention to Nielsen's previous work at the Department of Homeland Security.
'There will be no on the job training for Kirsten. She is ready on Day One,' Trump said.
Trump called on Congress to 'put politics aside' and confirm deputy White House chief of staff Nielsen by a 'strong, bipartisan vote.'
But even before Trump formally announced Nielsen's appointment during an East Room ceremony that was attended by much of the Cabinet and senior members of the White House staff, the top Democrat on a key committee signaled that he had questions about Nielsen's background.
Her nomination must be confirmed by the Senate.
Nielsen told the president she was 'humbled by the trust you are placing in me.'
If confirmed by the Senate, she will become the sixth secretary of a department that was created in the wake of the 9/11 terrorist attacks.
She'll be the first who formerly worked at the agency.
An expert in homeland and national security policy, Nielsen previously served as a special assistant to President George W. Bush and worked for the Transportation Security Administration.
The White House said Wednesday in a written announcement that Nielsen 'has extensive professional experience in the areas of homeland security policy and strategy, cybersecurity, critical infrastructure, and emergency management.'
Rep. Bennie G. Thompson of Mississippi, the senior Democrat on the House Committee on Homeland Security, said Wednesday in a statement he was pleased the president had made a decision on filling the post 'after letting the critical national security position remain vacant as the nation faced multiple major hurricanes and a domestic terrorism attack.'
Thompson said he had questions about Nielsen's background, including her past work for the Bush administration.