Delta Air Lines reported third-quarter earnings and revenue that topped Wall Street's expectations, but the airline warned of higher costs ahead in the last quarter of the year.

Delta's net income slipped 6 percent to US$1.18 billion, or US$1.64 a share in the three months ended in September.

On an adjusted basis, the largest U.S. airline by market capitalization reported adjusted earnings per share of US$1.57, beating Thomson Reuters analysts' expectations of US$1.53 a share for a quarter that ended with hurricanes that crippled operations.

Shares were up 1.7 percent in premarket trading.

Delta's per share earnings on an adjusted basis were about 8 percent lower over the year-earlier period.

The airline posted quarterly revenue of US$11.06 billion, slightly higher than expectations for US$11.03 billion in the three months ended in September and up 6 percent from a year earlier.

Delta's passenger revenue per available seat mile - a key income metric - rose 1.9 percent, in line with the airline's updated forecast earlier last month. It said it expects a 2 percent to 4 percent increase in passenger unit revenue in the fourth quarter, but warned that higher fuel costs would likely crimp operating margins for the last three months of the year.

Delta posted higher revenue in domestic and Latin American and trans-Atlantic operations, despite powerful storms in the Southern U.S. in August and September.

Hurricane Irma, which struck Florida and Delta's hub in Atlanta, forced the airline to cancel more than 2,000 flights.

Airline stocks surged on Tuesday after Delta competitors United Airlines and American Airlines, which report later this month, issued better-than-expected quarterly estimates.

Forecasts for Delta's domestic competitors are pointing to lower quarterly earnings as airlines grapple with how to grow profits with persistently low fares, and higher labor and fuel costs.

Delta executives will likely address the impact from deadly storms that hit carriers' hubs late this summer, as well as a bitter trade dispute between two Delta suppliers, Boeing and Canada's Bombardier.

The U.S. Commerce Department recommended trade duties of about 300 percent on Bombardier's new C-Series jets, after U.S. aircraft manufacturer Boeing complained its Canadian competitor received subsidies for the program and sold the jets below the cost of production. Delta agreed to purchase at least 75 of the some 100-seat jets last year.

"We got a great price," Delta's CEO Ed Bastian told CNBC, but declined to disclose the price. Bastian last month called the Commerce Department's decision "absurd," and said Boeing no longer makes a comparable product.