Speaking before the Japanese Diet Wednesday, Prime Minister Yoshihiko Noda voiced a growing concern over China's rising military power and accelerating naval activity.

The prime minister said he encourages China, Japan's largest export market, to be more responsible in its role in the international community.

"I am concerned about their reinforcement of national defense power, which lacks transparency, and their acceleration of maritime activities," said Noda, adding he wishes to make a visit to China to discuss the matter.

Japan's growing anxiety over its huge neighbor is accompanied by territorial disputes over South China Sea and East China Sea, where several countries claim territory.

China has been observed to be more aggressive in its territorial claims which are mostly nautical in nature. Its heavy military expenditures also are troubling other neighboring countries. Earlier, China announced to the media its military spending will increase by 12.7 percent or a total of $91.7 billion.

In January, China showcased to the world its first stealth fighter jet, aircraft carrier, and anti-ballistic missile which can crush even U.S. naval ships.

To abate the alarm from its neighbors, Beijing assured that its procurement of state-of-the-art fighter jets, cyber weapons, missiles and satellites is all defensive.

Despite booming trade, Sino-Japanese relations have been marred by controversies and grudges.

Last month, China was provoked to anger when Japan's Ministry of Defense said in its monthly publication that China's maritime activities reflected the "opaqueness" of Beijing's swift increase in military budget.

China retorted by branding Japan as "irresponsible," and reiterated that it is only modernizing its forces as part of its defense.

Noda has angered neighboring countries by assertions that seemed to exonerate Japanese war criminals of World War II.

Asia nations were relieved, however, when Noda swore neither he nor any of his Cabinet would visit the Yasukuni Shrine in Tokyo while holding a public office. Yasukuni is a memorial to Japan's war dead, including military leaders guilty of many crimes against humanity.