FILE PHOTO: Ukraine's President Volodymyr Zelenskiy speaks during a joint news conference after a Normandy-format summit in Paris, France December 10, 2019. REUTERS/Charles Platiau/Pool/File Photo

KIEV (Reuters) - Ukraine will test the airworthiness of its entire civilian fleet of aircraft following the crash of a Ukrainian airliner in Iran, President Volodymyr Zelenskiy said on Wednesday in a statement.

He also instructed his prosecutor general to open criminal proceedings - without specifying who they would involve - and said a commission should be set up to investigate the causes of the crash.