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May 6 (Reuters) - Hotel operator Marriott International MAR.O raised its full-year forecast for room revenue growth on Wednesday, betting that strong travel demand in the U.S. would drive bookings across its properties.

After a challenging year in which inflation and growth worries pinched customer budgets, U.S. travel is regaining momentum, a shift echoed in airlines' latest results.

U.S. hotels are optimistic about international tourism, expecting an influx of visitors ahead of the FIFA World Cup, set to take place in June and July this year.

The Bethesda, Maryland-based company expects 2026 revenue per available room (revPAR) — a key lodging metric that acts as a proxy for pricing power — to grow between 2% and 3%, compared with its prior forecast of a 1.5% to 2.5% increase. Its shares gained 1.6% in premarket trading.

RevPAR in its U.S. and Canada luxury properties increased 6.8% for the first quarter, buoyed by continued spending from affluent travelers. Its budget segment, which includes brands such as Courtyard and Fairfield, also reported a 3.5% rise in room revenue.

Still, outlook for the rest of the year remains uncertain as stubborn inflation and a drawn-out war in the Middle East risk driving up costs for consumers and curbing global travel spending. Peer Hilton and online travel agency Booking Holdings have already flagged an impact from the conflict.

Marriott said its outlook assumes continued impact from the Middle East conflict and travel disruption, primarily impacting the region through the end of the year.

Its first-quarter room revenue in Middle East and Africa fell 1.9% over the year earlier, while occupancy was down 5.4%.

The company posted a quarterly adjusted profit of $2.72 per share, beating analysts' average estimate of $2.55, according to data compiled by LSEG.