The central government has begun drawing up guidelines intended to deal with so-called gray zone contingencies that do not allow the government to immediately mobilize the Self-Defense Forces but could pose a serious security threat, a government source said on Wednesday.

Legal constraints permit Tokyo to mobilize the SDF only when a foreign country stages an armed attack against Japan. An attack by an unidentified armed group on a remote island, for example, may not meet that condition, some officials have argued, delaying a military response by the SDF.

Under the proposed guidelines that could take effect by the end of the year, the central government aims to strengthen coordination among relevant entities and streamline information sharing to enable the prime minister decide more quickly how to proceed in such situations, including whether the Self-Defense Forces should be mobilized, the government source said.