After Republican President-elect Donald Trump indicated Thursday that JPMorgan Chase CEO Jamie Dimon won’t be offered the role of Treasury secretary, the CEO of the biggest U.S. bank was quick to offer a retort.

Trump, in a Thursday afternoon post on his social media network, Truth Social, said an invitation to join his administration wouldn’t be extended to the 68-year-old Dimon.  

“I respect Jamie Dimon, of JPMorgan Chase, greatly, but he will not be invited to be a part of the Trump Administration. I thank Jamie for his outstanding service to our Country!” Trump wrote. The president-elect has proposed a number of Cabinet appointments this week.  

When Dimon, on stage Thursday at the Asia-Pacific Economic Cooperation CEO summit in Lima, Peru, was told of Trump’s sentiment, the CEO smiled, then said, “First of all, I wish the president well, and thank you, that’s a very nice note.” 

“But I just want to tell the president also, I haven’t had a boss in 25 years and I’m not about ready to start,” Dimon said, according to video posted by Bloomberg.

Last month, Dimon, who’s been CEO of the New York City-based bank since 2006, downplayed the likelihood he’d have a role in the next presidential administration. “I almost guarantee I’ll be doing this for a long period of time, or at least until the board kicks me out,” Dimon said during the bank’s third-quarter earnings call.

That appeared to be confirmed the day after the Nov. 5 election, when Reuters reported Dimon had no plans to join the Trump administration and would remain at the $3.9 trillion-asset bank, according to an unnamed source. Earlier this year, Trump said he would consider Dimon – and then claimed he didn’t say that – for Treasury secretary, if he were reelected.

Dimon refrained from endorsing either candidate in the presidential election, although The New York Times reported the CEO privately expressed a preference for Democratic candidate Vice President Kamala Harris. Dimon’s wife, Judith Kent, knocked on doors in Michigan for the Harris campaign in the days leading up to the election, The New York Times reported.

In August, Dimon wrote an op-ed for The Washington Post, calling for a president that will unite the country and fortify America’s role as a global leader. Dimon has repeatedly called himself an American patriot and expressed concern over the geopolitical atmosphere and the “deeply divided” state of the country.

Trump is “entering and going to be responsible for the most complicated geopolitical military and geoeconomic situation that the world has faced since World War II,” Dimon asserted Thursday at the summit.

Dimon said he wishes the next administration the best. “It could be a difficult thing with a lot of unknowns and uncertainties, and so policy’s going to matter,” he said. “And, of course, who runs the government will be determinative there.”   

Dimon has commended some of Trump’s record, although he’s also privately expressed a distaste for the former and future president.

The CEO said Thursday the markets have responded “quite well” to Trump’s win, which industry analysts expect will bring deregulation and a pro-growth emphasis. America “needs a growth strategy,” and collaboration between government and business fuels growth, he added.

Dimon has been a strong critic of regulation – the “onslaught” of bank rules and regulations is “damaging America,” he’s said this year – although he noted Thursday he’s not advocating for “just getting rid of regulations.” 

The regulatory climate in most countries has become “stifling” to potential growth, he said, which is why he’s called for reform. “That reform has to go deeper than just regulations,” he added. “It’s got to be permanent.”

“I applaud any government that says, ‘I’m going to make government more efficient.’ And I think inefficient government is one of the reasons that people are frustrated,” Dimon continued. 

Although the CEO had long put his eventual departure at five years away, at the bank’s investor day in May, Dimon said the timetable “isn’t five years anymore.” He noted succession planning at JPMorgan is well underway.  

Potential successors to Dimon include Marianne Lake, head of the bank’s consumer and community banking division; Jennifer Piepszak or Troy Rohrbaugh, co-CEOs of JPMorgan’s commercial and investment bank; or Mary Callahan Erdoes, the bank’s CEO of asset and wealth management.