Kirstjen Nielsen, Chief of Staff of U.S. Department of Homeland Security, center, walks to Air Force One as she departs Tuesday, Aug. 22, 2017, at Andrews Air Force Base, Md. Associated Press/Alex Brandon

President Donald Trump on Wednesday nominated Kirstjen Nielsen, a longtime aide to chief of staff John Kelly, to head the Department of Homeland Security.

In a formal announcement on Thursday, Trump called on senators to quickly confirm her with a "strong, bipartisan vote" due in part to the urgency of disaster recovery efforts underway in Texas, Florida, and Puerto Rico.

"At this crucial time, we need the Senate to confirm a secretary of homeland security. One who is ready to lead on day one," Trump said.

"Kirstjen has my full faith and confidence, and she also has the complete confidence of the law enforcement officers, dedicated professionals, and senior leadership at the Department of Homeland Security."

The White House has touted Nielsen's former homeland security experience, and expertise in cybersecurity, critical infrastructure, and emergency management. In a statement on Wednesday, the White House also noted that Nielsen is the first nominee for the position to have previously worked in the department.

Nielsen previously served in the Transportation Security Administration and on the White House Homeland Security Council under the George W. Bush administration.

The Homeland Security Department's top job has been vacant since July, when Kelly was given the chief of staff role after the ousting of his predecessor, Reince Priebus. Acting secretary Elaine Duke has been leading DHS in the meantime.

Nielsen has become well-known in recent months for being a brusque enforcer of Kelly's agenda in the West Wing, where her reportedly curt, no-nonsense manner caused some backlash among Trump aides.

According to Politico, multiple Trump loyalists even privately referred to Nielsen as "Nurse Ratched," the fictional character from "One Flew Over the Cuckoo's Nest" known for her austere and corrupt influence over the mental institution she managed.

In her remarks on Thursday, Nielsen thanked Trump for his nomination and said a confirmation to the appointment would be the "highest honor of my life."

"If confirmed as the sixth secretary of homeland security, I will work every day to enforce the law, secure our borders, our coasts and waterways, ant do protect Americans from dangerous criminals, terrorists, cyberattacks, and all the other threats facing our homeland today," Nielsen said.

Watch a clip of her remarks below: