British Airways owner IAG suffered a 60% slump in operating profits in the first quarter of the year.
The figure fell to €135 million from €340 million in the same winter three months last year.
Profits after tax before exceptional items fell by 62.6% to €70 million.
The parent company of carriers including Aer Lingus, Iberia, Vueling and Level saw fuel costs rise by almost 16% in the period.
It also suffered from a €61 million hit from fluctuating foreign exchange rates.
Passenger revenue rose by 5.2% year-on-year to €4.6 billion.
The passenger load factor rose 0.2 percentage points to 80.7%. This came as the group carried almost 24.4 million passengers, up 6.2% over the same period last year.
Chief executive Willie Walsh said: “In a quarter when European airlines were significantly affected by fuel and foreign exchange headwinds, market capacity impacting yield and the timing of Easter, we remained profitable and are reporting an operating profit of €135 million.
“At constant currency, non-fuel unit costs were down 0.6% while passenger unit revenue decreased by 1.4%.”
IAG capacity increased by 6.1% in the first three months, mainly driven by Iberia, up 11.1%, the expansion of Level and Aer Lingus, up 14.2%. Vueling and BA also raised capacity by 4% and 1.5% respectively.
IAG announced in the quarter that it did not intend to make an offer for Norwegian Air and consequently sold its 3.93% shareholding.
The group expects its 2019 operating profit before exceptional items to be in line with last year.
“Passenger unit revenue is expected to be flat at constant currency and non-fuel unit cost is expected to improve at constant currency,” the company said.
“We expect passenger unit revenue at constant currency to improve for the remainder of the year.”
IAG’s April traffic rose by 7.7% over the same month in 2018 as capacity rose by 5.8%. Passenger numbers were up 7.3% to 9.8 million.
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IAG 2019 profit projected to be pegged at last year’s level