Israel on Sunday defended its conduct in the 2014 Gaza war as both "lawful" and "legitimate" in an inter-ministerial report into the deadly 50-day conflict.

"Much of what may have appeared to external parties to be indiscriminate harm to civilians or purely civilian objects was in fact legitimate attacks against military targets that merely appear civilian but were actually part of the military operations of these terrorist organisations," the report said.

Civilians were also harmed as a result of "unfortunate -- yet lawful -- incidental effects of legitimate military action in the vicinity of civilians and their surroundings," it added.