Jamie Dimon, the J.P. Morgan Chase CEO who has been bullish on the U.S. economy, said the partial government shutdown could wipe out growth from the world's biggest economy.

"Someone estimated that if it goes on for the whole quarter, it can reduce growth to zero," Dimon told reporters on a media call to discuss fourth-quarter results. "We just have to deal with that. It's more of a political issue than anything else."

Dimon, who is also chairman of the Washington, D.C.-based Business Roundtable, said that while the "underlying statistics for the economy globally are not bad," the bank will be prepared for the eventual downturn.

There's still growth, despite early signs of a slowdown in China, Japan and the U.S., among other nations, he said. "Consumers are in good shape, they're spending money, they're saving money, household formation is going up, wages are going up," Dimon said. "Eventually there will be offsets that may push the economy into recession, we don't know when that's going to be."