President Trump has lost his longtime national security aide, Robert Gabriel. 

The White House insider is moving on to 'new chapters,' according to a post shared by White House Chief of Staff Susie Wiles.

Gabriel is leaving his position as principal deputy national security advisor, working under Secretary of State and National Security Advisor Marco Rubio.

'Today is a day I hoped would not come,' Wiles wrote on X about his departure, calling him 'young, brilliant, and talented.'

He's moving on to a new 'chapter,' Trump's Ice Maiden wrote on X in the affectionate post. 

Gabriel, who is in his early 30's, worked for Trump for over a decade, was also 'by my side' through the campaign and White House transition. 

He played a 'pivotal policy role' during Trump's first 100 days to 'great success,' she added.

Wiles continued to call him a 'trusted confidant' and 'dear friend.'

Gabriel got his first stint working for Trump in 2015. 

He continued on during the 2016 campaign and Trump's first and second term and  worked hand-in-hand with Wiles during his last term, taking on a big role with the transition team.

'Susie and Gabriel are in lockstep - she doesn't do anything without him so this is a huge loss,' a source close to the White House explained. 'He really ran the campaign for Wiles and was on the road constantly.'

Another source called him 'irreplaceable.'  

Secretary of State Marco Rubio posted on X, congratulating Gabriel and applauding all his efforts.

'I am proud of the outstanding leadership Robert Gabriel has delivered as Principal Deputy National Security Advisor,' he posted.

'In just one year, he has supercharged the White House NSC, accelerated interagency work on President Trump's top priorities, and partnered with the Cabinet to achieve historic wins.'

Rubio added that Gabriel's deep bench of skills, including foreign policy expertise, connections in government and 'unmatched ability to solve complex problems' made him successful.

'I am grateful for his service and friendship,' Rubio said.

Gabriel joined the NSC shortly after Mike Waltz's departure as National Security Advisor in May 2025.

A source close to Gabriel describes him as someone who 'doesn't like the limelight' and helped run a 'leaner operation' at the NSC. 

Before working in the administration, Gabriel worked at Fox News as an associate producer.