Markets from equities to high-yield bonds that have been flashing warning signs are probably an overreaction to slowing growth rather than a precursor of imminent recession, according to J.P. Morgan Chase CEO Jamie Dimon.

"I think markets are overreacting to short-term sentiment around a whole bunch of complex issues," Dimon said in a Fox Business interview released Tuesday. He quickly added that the market moves were a "rational response" to slower growth and the U.S.-China trade dispute.

But overall, Dimon, who leads the biggest U.S. lender, said the December stock declines and the halting by banks of high-yield debt issuance last month were unwarranted. He said he's "really not worried about" what happened to riskier corporate debt because credit spreads are returning to normal after a long period of suppression.