BEIJING - A naval fleet of the Chinese People's Liberation Army (PLA) will conduct a training drill within international waters in the western Pacific Ocean from the middle to the end of this month, the Ministry of National Defense said on Thursday.

The ministry, in a news release issued by its Information Affairs Office, said that the training complies with relevant international laws and is not aimed at any particular country or specific target.

The ministry's reaction came after an earlier announcement made by Japan's Ministry of Defense on Wednesday, which said that eight Chinese navy ships, including guided missile destroyers, were on the high seas near Okinawa prefecture.

Japan's major media reported the news and said that the Chinese naval fleet was heading to the Pacific Ocean.

According to Kyodo News, Japan's Maritime Self Defense Force (MSDF) is on alert and is continuing to monitor the fleet's movements.

China's Defense Ministry stressed that the upcoming drill is a "regular exercise" held "in accordance with the annual plan (of the PLA)".

"The Ministry of National Defense is quick to react and transparent in its military activities," said Yang Bojiang, a professor of Japanese studies at the University of International Relations in Beijing.

He said that the Japanese should not be concerned about the Chinese naval training exercises because all activities of China's navy are strictly confined to international waters.

It is not the first time that Japan has shown concern over China's naval training exercises.

An editorial article published on Asahi Shimbun's website last April even called Beijing's attitude "unacceptable" when a Chinese helicopter came close to a MSDF destroyer during training.

China has defended the move and said the country's military training in open seas near Japan was in line with the international conventions.

"Indeed, Japan is too nervous about China's normal naval training," Yang said.

"Japan's 2010 National Defense Program Guidelines asks to beef up defense in its southwestern area, but the Japanese government is facing serious financial problems, and the March 11 earthquake and tsunami have added to its fiscal woes. So I think some people in Japan, who have an interest in increased defense spending, want to play up China's military activities."