NEW YORK (TheStreet) -- The U.K. referendum to exit the European Union continues to push global and U.S. markets downward, with the Dow Jones Industrial Average lower 317.9 points Monday morning. 

As many seek optimism, U.S. Treasury Secretary Jack Lew believes the American economy will continue to perform in a stable manner despite substantial economic headwinds.

"There's no question this is an additional headwind but I think it is something we can manage through and Europe and the U.K. can manage through," Lew told CNBC's Steve Liesman on "Squawk Box" this morning. "There's no sense of a financial crisis developing."

The British policy change is influencing investors worldwide but Lew thinks that the impact has been orderly. And he does not see it as endangering current negotiations underway with Europe for the Trans-Pacific Partnership trade agreement. New negotiations between the U.S. and the U.K. "will have to take a course that is in part determined by what happens between the U.K. and the E.U.," Lew said.

Investors should be cautious about the strong immediate reactions across markets to Brexit, as Lew warns not to "overreact to a volatile day here or there" because this will be "be a fairly long period of change."

Lew also wants policymakers to focus "on what can we do to correct some of the inequities that have made it a better economy for people at the top than people in the middle." His perception is that there's "a lot of anxiety on the part of working people about an economy that doesn't necessary work for them."

"We've seen greater growth in the macro economy than we have seen distribution of the benefits across income classes," Lew added.