Updated from 11:28 a.m. EDT

JetBlue

(JBLU) - Get Report

says it will be in the black in the second half of the year, but that high fuel costs are going to squeeze its margins.

JetBlue continues to expect a second-half operating profit. The forecast, made in a regulatory filing late Monday, assumes fuel will cost the airline $1.68 a gallon, including hedges designed to reduce exposure to skyrocketing energy prices.

But the New York airline warned that if fuel stays at that level for the rest of the year, it would expect to report a lower operating margin than its previous guidance, which assumed fuel would cost $1.45 in the second half of the year.

In a quarterly filing on April 25, JetBlue predicted a full-year operating margin between 5% and 7%. Shares fell 51 cents, or 2.5%, to $20.22.

The airline, which has been profitable in every quarter since the beginning of 2001, said it made Monday's filing to "clarify" comments CEO David Neeleman gave in an interview with

Reuters

that was published last Friday.

Reuters

quoted Neeleman as saying JetBlue could continue to make a profit even if crude oil prices rose as high as $80 a barrel.

The CEO also said in the interview that he believes the airline can eventually improve its operating margin because oil prices will either decline or go so high that rivals like

Delta Air Lines

(DAL) - Get Report

are forced out of business.

Fellow low-cost carrier

Southwest

(LUV) - Get Report

will kick off the earnings reports for the airlines before the opening bell Thursday, when it's scheduled to release second-quarter results.