Feb 24 (Reuters) - Singapore Airlines posted a nearly 69% slide in third-quarter net profit on Tuesday, due to the absence of last year's one-off gain from the Air India–Vistara merger and rising fuel costs.

The airline's share of losses from associated companies climbed by S$163 million to S$178 million, reflecting a full-quarter share of Air India's losses this year, compared with only one month in the year-ago period.

Vistara Airlines, in which Singapore Airlines had a 49% stake, completed a merger with Air India in 2024 to establish a dominant full-service carrier for India's growing domestic and international markets.

Additionally, record global travel demand kept older aircraft in service, pushing up fuel, maintenance, engine-leasing and inventory costs.

The airline's expenditure rose to S$4.71 billion compared with S$4.59 billion, driven by higher non‑fuel costs and an increase in net fuel cost due to firmer prices and uplift volumes in the period.

The city-state's flag carrier posted a net profit of S$505 million ($398.64 million) for the three-month period ended December 31, compared with S$1.63 billion a year ago.

Total revenue for the quarter, however, rose 5.5% to S$5.51 billion from the same period last year.

($1 = 1.2668 Singapore dollars)