Donald Trump’s former chief of staff, John Kelly, says he would have considered working for Hillary Clinton had she been elected president.

Kelly spoke during an event at Duke University on Wednesday, and ABC News reports he said that if Trump’s Democratic rival had won in 2016 and asked him to be her chief of staff, he “probably” would have said yes.

The New York Times reported that Kelly explained that he didn’t think of himself as working for Trump.

Kelly also said during this event that working in the White House was the “least enjoyable” job he’s ever had, although he said it was also the most important, per NBC News.

And when asked what advice he had for his successor, Mick Mulvaney, he joked, “Run for it,” per the Times. After Kelly’s response drew laughter from the crowd, he offered a more serious answer, recommending Mulvaney tell the president “what he needs to hear.”

While not directly going after Trump as some former administration officials have done, Kelly did voice some disagreements with the president on Wednesday, objecting to Trump’s deployment of troops to the southern border last year by saying he “would always look for another way to do it.”

Speaking about immigrants trying to cross the U.S. border, Kelly also said they are “overwhelmingly not criminals.”

Kelly also pushed against Trump’s plan to build a border wall, saying that a structure spanning the entire U.S.-Mexico border would be a “waste of money.”

“We don’t need a wall from sea to shining sea,” Kelly said, according to Politico.

The former Trump administration official noted that there are areas along the southern border where steel barriers would be necessary. But Kelly mainly broke with the president’s policy proposals on immigration.

WATCH:

NEW OVERNIGHT: Former WH Chief of Staff John Kelly breaks his silence for the first time since leaving the White House. https://t.co/hOA4cYZxGS@CeciliaVega reports live from the White House lawn. pic.twitter.com/lObmJtCTXE

— Good Morning America (@GMA) March 7, 2019