Japan's claims to islands seized by Soviet forces in World War II and installation of U.S. missile defense have troubled relations with Russia.
Japan says historic decisions to purchase new, powerful weapons were purely defensive, but North Korea said Tokyo was preparing another invasion.
A proposal to build two Aegis Ashore batteries was approved by Prime Minister Shinzo Abe's Cabinet on Tuesday
Japan is the only country ever attacked with a nuclear weapon, and more than 72 years later it has the ability to build a bomb of its own.
The sale of $113 million worth of advanced air-to-air missiles to Japan needs to be approved by Congress.
Influential Japanese lawmakers have begun publicly campaigning to end Tokyo's U.S.-imposed pacifism and prepare for a potential preemptive strike on nuclear-armed North Korea.
From now on, Japan's military, known as its Self-Defense Forces, will be permitted to fight overseas
The bills have sparked massive protests from ordinary citizens who say they violate the country's post-World War pacifist constitution.