The talks come as Prime Minister Shinzo Abe has called for giving Japan greater military freedom, Time magazine reported. The constitution adopted after World War II allows Japan to use military force only if its own territory is attacked or to assist allies who have suffered a direct attack.
Japan is involved in a dispute with China over a group of uninhabited islands, called the Senkakus in Japan and the Diaoyu in China. Japan has recently responded to Chinese observation flights over the group with F-15 fighter jets, although no shots were fired.
The dispute, coupled with China's growing military capacity, has made expanding Japan's military role more popular with the Japanese public.
Jeffrey Hornung of the Asia-Pacific Center for Security Studies in Honolulu said he expects the Abe government to adopt a more expansive view of the allowable use of military force.
"Collective self defense is a no-brainer. It's not an offensive capability. It's not projecting power. It's just what to do if the U.S. comes under attack," Hornung said.
The talks are expected to be conducted through 2013.