Pakistan, Sept. 17 -- American Airlines has warned that persistently high fuel prices could force it to adjust future capacity plans. Chief Executive Robert Isom made the comments on Wednesday. He spoke during a Morgan Stanley conference about the airline's financial outlook. However, strong travel demand and higher fares have helped offset much of the increased fuel expense.

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Isom said he remained confident about the company's third-quarter revenue outlook. American Airlines expects revenue growth between 16% and 19% during the quarter. He also said most of the recent revenue gains should remain sustainable. Strong passenger demand has supported higher fares ...