The United States and Japan successfully tested Japan's Aegis Ballistic Missile Defense system off the coast of Hawaii on Tuesday, according to US military officials.
The test of the Aegis system, by Lockheed Martin Corp, "provides confidence in the future capability for Japan to defeat the developing threats in the region," said Lieutenant General Sam Greaves, director of the U. Missile Defense Agency.
Japan last year decided to expand its ballistic missile defense capabilities with the US-made Aegis system in response to what it said was a growing threat from North Korean rockets.
Japan is wary of North Korean promises to abandon its nuclear weapons and ballistic missile programs and considers North Korea its most serious threat even as US President Donald Trump has vowed progress on denuclearisation.
Mr Trump has also pushed Japan to buy more US military gear and other goods.
"We are committed to assisting the government of Japan in upgrading its national missile defense capability against emerging threats," Lt Gen Greaves said.
Japan has also said its missile defense systems are for self-defence only and do not pose a threat to Russia, which has expressed concern over efforts to establish a US missile defence system in the region.
On Wednesday, Russia made a dramatic offer to formally end World War II hostilities between their countries, an overture clouded by a decades-old dispute over an island chain in the Pacific Ocean.
In the test on Tuesday, a simple, separating ballistic missile launched from the Pacific Missile Range Facility at Barking Sands in Kauai, Hawaii, was intercepted above the Pacific by an upgraded standard missile 3, the MDA said.