If implemented, the proposed tariffs could spike inflation, but national security is more important, the bank CEO said.

Dimon's comments Wednesday come as Trump has threatened to impose a 25 percent tariff on products from Mexico and Canada by February 1 and a 10 percent tariff on Chinese imports. Earlier Wednesday, Trump also teased the notion of imposing "taxes, tariffs, and sanctions" on Russia if it doesn't end its war against Ukraine.

The JPMorgan Chase chief executive, who had warned of the negative effect of tariffs, said they could be justified for national security reasons.