BEIJING, May 27-- A Foreign Ministry spokesperson on Wednesday justified China's concern over Japanese military buildup, after Japan's chief cabinet secretary questioned the rationale of China's defensive military strategy.

Following the Tuesday release of China's first white paper on military strategy, Japanese broadcaster NHK reported that Chief Cabinet Secretary Yoshihide Suga had dismissed concern expressed in the paper about Japan's efforts to enact new security legislation.

Foreign Ministry spokeswoman Hua Chunying said China had suffered long-term aggression by imperialist powers.

"History dictates that we must build a national defense force to match up to our economic development and the need of safeguarding national security," Hua said.