Exclusive: As North Korea expands arsenal, Japan's missile defence shield faces unforeseen costs - sources

FILE PHOTO: A man watches a television screen showing a news report on North Korea firing several short-range projectiles from its east coast, on a street in Tokyo, Japan May 4, 2019. REUTERS/Kim Kyung-Hoon/File Photo

TOKYO (Reuters) - Additional tests may add at least $500 million (£405.5 million) to Japan's price tag for two U.S.-built ballistic missile interceptor stations that could struggle to shoot down the latest North Korean missile types, four government and defence sources said.

The tests are required to show the system is working properly, according to Lockheed Martin, the manufacturer. Held in Hawaii rather than Japan, they would cost about $100 million per launch.