ATLANTA (Bloomberg) — Delta Air Lines Inc., the third-largest US carrier, said a revised agreement for processing Visa and MasterCard credit cards freed up $1.1 billion held in reserve.The change will enable Delta to end this quarter with $4.2 billion in cash, marketable securities and a revolving credit line, the Atlanta-based airline said yesterday in a statement. While Delta was in bankruptcy, payments were withheld for credit-card purchases of tickets that hadn't been used for travel.

Delta, which left bankruptcy April 30, also trimmed the top range of its projected operating margin this quarter to 12 percent, from 13 percent, and said it would shift some capacity to international routes from US flying.

"Our plan remains on track, with our restructuring driving improvements to both unit revenues and unit costs," chief financial officer Edward H. Bastian said in the statement.

Delta's new estimate for its second-quarter operating margin is 11 percent to 12 percent, compared with a projection of 11 percent to 13 percent on April 23. The airline's restructuring plan calls for its annual margin to rise to 10.5 percent by 2010 from eight percent this year.

Delta revised the projection to reflect new information as it nears the end of the quarter, spokeswoman Betsy Talton said.

The airline said it will reduce domestic capacity by 4 percent to 6 percent this quarter while expanding international capacity by 14 percent to 16 percent, as part of an effort to shift more flying to higher-profit overseas routes.