The government is thinking of buying and deploying cruise missiles in response to North Korea's provocative missile and nuclear tests, an official has said.

The government is eager to set aside funds to study the feasibility of acquiring the ability to strike enemy missile sites, and could do so in the draft budget for fiscal 2018, the official said Friday on condition of anonymity.

However, there are concerns in the government and ruling bloc that acquiring such offensive potential would contradict Japan's exclusively defense-oriented "posture" and trigger a backlash from opposition parties, even though they have in recent years been virtually incapable of reining in the ruling camp.