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LONDON, Jan 29 (Reuters) - British budget airline EasyJet EZJ.L posted a wider first-quarter loss on Thursday, as it absorbed costs from a strategic expansion into Italian airports, though the carrier said bookings for the crucial summer season were building strongly.

EasyJet reported an operating loss of 76 million pounds ($105.14 million) in the three months ended December 31, compared with last year's first-quarter operating loss of 40 million pounds.

"This year, the traditionally busy January booking period has seen record levels in both volume and revenue, as bookings continue to build for Summer 2026," the company said in a statement.

The first quarter of the year is often the most loss-making one for airlines as travel dips in the winter months. In November, EasyJet lifted its medium-term target for its lucrative holiday business but projected weaker winter sales.

The airline's holiday business continued to grow, posting a 50 million pound pretax profit in the quarter as customer numbers jumped 20%.

($1 = 0.7229 pounds)