(Sharecast News) - Delta Air Lines cut its full-year profit forecast on Friday, pointing to higher fuel prices due to the Iran war.

The company now expects full-year earnings per share of between $5.10 and $5.60, down from previous guidance of $6.50 to $7.50. The free cash flow outlook was also cut, to $2.5bn from $4bn forecast in July.

The outlook downgrade came as Delta reported a 16% year-on-year rise in operating revenue to the end of September to $17.6bn, but a near-50% drop in net income to $756m as fuel expenses jumped 69%.

Chief financial officer Erik Snell said: "Delta delivered earnings of $1.72 per share in the September quarter, in line with last year while absorbing more than $500 million of higher fuel costs compared to our guidance in early July. In the December quarter, we expect earnings of $1.15 to $1.65 per share, based on a fuel price of approximately $4.25 per gallon. This positions earnings consistent with last year at the upper end of the range.

"The Delta team continues to deliver for our customers, widening our industry lead in on-time performance and achieving record baggage results. September quarter non-fuel unit costs increased 7.3% over the prior year on flat capacity, driven primarily by higher crew and revenue-related costs on capacity growth that was several points below our original plan, including nearly one point of impact from summer storms.

"With slightly higher capacity and continued operational efficiencies, we expect December quarter non-fuel unit cost growth to improve 1 to 2 points sequentially. Looking to next year, we remain on track for low-single-digit unit cost growth as capacity normalizes, operational improvements continue and we lap higher costs in our baseline."

At 1255 BST, the shares were down 1.6% in pre-market trade at $80.85.