The airline, a joint venture between Turkish Airlines and Lufthansa, has “temporarily” suspended services from Glasgow and Leeds Bradford, as well as its Manchester-Bodrum route.
A spokesperson added there were “a number of short-term frequency reductions on other services”.
“Due to the ongoing geopolitical developments, the aviation industry is currently operating in a highly volatile environment characterised by significant cost increases, particularly for jet fuel," they said.
"SunExpress is therefore taking steps to improve fuel efficiency and optimise flight operations.”