FRANKFURT (Reuters) -Luxury sportscar maker Porsche AG on Friday warned it may cut costs after a slower-than-expected transition towards electric vehicles and persisting weakness in the Chinese market caused nine-month operating profit to fall by more than a quarter.

"For this reason, we are reviewing our product line-up and ecosystem, as well as our budgets and cost position. All with the aim of increasing our flexibility and resilience even further," Porsche AG CFO Lutz Meschke said.

Porsche, which is majority-owned by Volkswagen, said nine-month operating profit declined by 26.7% to 4.04 billion euros ($4.37 billion), while sales for the period came in 5.2% lower at 28.56 billion euros.

In China, Porsche's single most important market, the group is facing what Meschke called a "structural shift in demand", a reference to continued weakness in the world's biggest car market that has hit all European carmakers.

Third-quarter operating profit fell 41% to 974 million euros, below the 1.08 billion LSEG estimate, while sales for the period fell to 9.1 billion, resulting in an operating margin of 10.7%.

($1 = 0.9240 euros)