China has obtained "adequate" evidence of Japanese warships and airplanes conducting close-range monitoring and surveillance of the Chinese navy, China's military spokesman said on Thursday.

"China will retain the right of adopting relevant measures," said Geng Yansheng, spokesman with the Ministry of National Defense, at a news briefing.

Japanese warships and airplanes have for a long time closely followed, monitored and disturbed Chinese naval ships and airplanes, a practice which harms the security of the Chinese ships and airplanes and aggravates current Sino-Japanese marine security problems, according to Geng.

Earlier this month, China's Defense Ministry refuted Japanese allegations that Chinese warships targeted Japanese vessels using fire-control radar, describing the allegations as "a sheer fabrication."

Geng said the facts are clear and Japanese allegations are groundless.

With this fabrication, Japan has displayed its ulterior motives of tarnishing the image of Chinese military, maliciously creating regional tension and misleading international public opinion, he said.

"Japan's motives are worth much attention from the international community," Geng added.

According to the spokesman, China has placed much stock in marine security and is unwilling to see unexpected marine incidents occur, he said.

However, he went on, Japanese leaders at times published provocative sayings, which hyped the so-called "China threat," over-stressed military issues and instigated military confrontation.

"Japan should mind their words and actions, stop publishing mistaken sayings, properly handle the issue of the Diaoyu Islands, adopt realistic measures and create conditions to improve bilateral relations," Geng urged.