SINGAPORE, Feb 3 (Reuters) - A senior Rolls-Royce executive on Tuesday defended recent price rises and improvements in performance after airlines accused engine makers of profiting from supply chain problems.

The head of the International Air Transport Association, Willie Walsh, said on Monday ‌that engine makers had raised prices across the board for repairs despite shortfalls in durability ​and long queues for maintenance on the latest jet engines.

Rob Watson, president ‍of Rolls-Royce's civil aerospace division, said engine pricing ⁠reflected supply chain ⁠disruptions and the fallout from geopolitical instability.

"I think that our pricing reflects supply chain disruption coming ‌out of COVID," Watson said in ​an interview on the sidelines of the Singapore Airshow.

"For us, pricing has to some extent been a function of ⁠cost. We're reflecting raised costs, which ‍are driven ​by all those supply chain challenges that everybody talks about," he added.

Watson said the British engine maker was "on track" with a ‍programme of improvements in the durability of its largest engine for the long-haul Airbus A350-1000.

Rolls has said the improvements are already delivering 60% more time on wing between overhauls with further improvements expected from 2028.

It plans to test the engine in harsh Middle East conditions in 2027. ​Dubai's ‍Emirates, the world's largest buyer of wide-body jets, has called for progress in lengthening the time between repair shop visits before ​buying the jet.

Asked about proposals by Airbus to expand the A350 family with a bigger A350-2000 model to counter Boeing's ( BA ) 777-9, Watson voiced general support but declined to be drawn into specifics.

"We have a very close partnership with Airbus, which has been very successful. So we'll always want to stay aligned with ​their thinking of the market, and ... make sure our product strategy is aligned with their product strategy."

Some analysts have said such a plane would require a potentially costly engine enhancement ‍or development.