Smith took over as chief executive in September 2018, pledging gains from closer integration of the French and Dutch carriers. In a surprise move last year, amid KLM resistance to governance changes, the Dutch state bought a 14% stake in the group to match the French government's holding.

While the order swap of KLM Airbus jets for Air France Boeings in June showed a high level of coordination, Smith told the Anglo-American Press Association in Paris, closer cooperation could bring the group more "purchasing power" as the operator of more than 500 aircraft.

"Are they operating as efficiently as I thought possible? No," he said of the airlines' fleet planners. "Is there more to do? I think yes."

While each airline still has its own fleet team, Smith added, decisions need approval from the group board. "We’ve elevated the decision-making process a bit earlier on, to ensure there’s more synergies."

Under a mid-term plan presented to investors in November, Smith has pledged to improve Air France profitability and narrow the gap with its stablemate. The French carrier posted an 8.2% operating margin to KLM's 16.2% for the third quarter.

(Reporting by Laurence Frost; Writing by Richard Lough; Editing by Kevin Liffey and Alexander Smith)