Calabasas-based Countrywide Financial Corp. will begin trading derivatives later this year to bolster sales of U.S. Treasury securities, Chief Executive Angelo Mozilo said at a Wall Street event on Thursday.

“You just can’t trade Treasuries,” Bloomberg News quoted Mozilo as saying at a conference hosted by Sanford C. Bernstein & Co. “You have to have a combination product to sell along with the Treasuries, one being futures, the other being derivatives.’

Mozilo said he has informed the credit-rating companies of its intent to begin trading derivatives.

Countrywide, the nation’s largest mortgage lender, is entering the business at a time when derivatives are displacing trading of corporate debt as a better way to gauge a company’s health.

The market totals $17 trillion, more than three times the amount of U.S. company bonds, according to Bloomberg. The Dow Jones CDX North American Investment Grade Index, which tracks the derivatives on 125 company bonds, rose almost 15 percent in the first two weeks of May. The next week, corporate bonds posted their worst performance in a year.