U.S. President Donald Trump’s chief of staff, John Kelly, and national security adviser, John Bolton, got in a heated argument Thursday outside the Oval Office, according to multiple sources, CNN and Bloomberg report.
The argument was over immigration and border crossings, which has had a recent surge, as well as the performance of Homeland Security Secretary Kristjen Nielson, Bloomberg’s source said.
Nielson was a former deputy under Kelly when he ran the Department of Homeland Security. Bolton criticized Nielson, saying she needs to start doing her job, which angered Kelly, according to CNN’s source.
WATCH: Honduran migrants push through Guatemalan jungle as Trump threatens to send military
Trump has been incensed recently over rising levels of migrants, and threatened to shut down the southern border earlier Thursday on Twitter.
Bolton favours a harder line approach to the issue than Kelly, and Trump sided with Bolton on the issue, Bloomberg’s source said.
WATCH: Trump says he has not heard of Bolton, Kelly shouting match
A source who heard the shouting said it went well beyond previous arguments in the White House, CNN reports, and fueled speculation that one of the men might resign. However, a White House official did say that tempers had since cooled and neither men are going to leave.
Trump, when asked about the incident, said, “That I have not heard about.”
Trump has been angered recently by reports of a migrant caravan formed in San Pedro Sula, Honduras, on Saturday that is heading to the U.S. carrying thousands of migrants, organizers say.
Trump threatened on Tuesday via Twitter to discontinue foreign aid to Honduras if the caravan is not stopped.