Adds context and more detail from results presentation from paragraph 2 onwards

NAIROBI, March 24 (Reuters) - Kenya Airways KQNA.NR on Tuesday reported a pre-tax loss of 17.93 billion shillings ($138.30 million) in 2025, hurt by falling revenues.

The result is a setback for one of Africa's leading airlines, as it made its first pre-tax profit in more than a decade in 2024.

The airline, which has a fleet of roughly 40 aircraft, said total income fell to 161.47 billion shillings last year from 188.50 billion shillings in 2024.

Chief Financial Officer Mary Mwenga said the deterioration in the company's performance was partly because three of its wide-body Boeing BA.N 787-8 Dreamliner jets were temporarily grounded because of global supply chain constraints.

Its 2024 profit was helped by foreign-exchange gains, as the shilling currency KES= strengthened more than 20% against the dollar that year.

($1 = 129.6500 Kenyan shillings)