Japan had asked to buy 63 F-35A, the traditional version of the electronics-laden fighter aircraft, and 42 F-35B, the short-takeoff and vertical-landing version for aircraft carriers, the State Department said in a statement.

Washington gave its green light to the transaction, which will improve "the security of a major ally" in the Asia-Pacific region, the statement noted.

"It is vital to US national interest to assist Japan in developing and maintaining a strong and effective self-defense capability," the State Department added.

Japan's 2020/2021 defense budget is a record $50.3 billion, aimed at funding purchases of fighter jets and missile defense as the country eyes the threat from North Korea and China.

In response to the rapid modernization of the Chinese military, Japan has decided to acquire a total of 105 F-35A aircraft over the next decade, in addition to 42 F-35B aircraft.

At the end of 2018, the Japanese government approved a five-year defense plan that includes the entry of two aircraft carriers into its arsenal -- a first since the end of World War II.