Delta Air Lines

(DAL) - Get Report

said Wednesday its debt exchange has ended, with the intermediate and long-term portions receiving insufficient interest from bondholders.

The airline had been hoping to exchange a total of $2.6 billion of unsecured debt securities and enhanced pass-through certificates for $680 million of new senior secured notes.

But even after Delta extended the exchange offer, only the short-term piece -- the enhanced pass-through certificates -- received sufficient tenders to satisfy the offer's terms.

Delta said bondholders had tendered $256.8 million of the short-term securities, $87.2 million of the intermediate securities and $263.4 million of the long-term securities. The airline will return the tendered intermediate and long-term securities to their holders and will use the collateral originally reserved for those securities to secure other financing.

The nation's third-largest airline has struggled as sky-high fuel prices have driven up expenses. A glut of capacity and tough price competition have made it tough for airlines to raise fares.

Delta shares closed Tuesday down 6 cents, or 0.9%, at $6.55.