In his first speech to Congress last week, US President Donald Trump kept asking friends and partners from Europe to the Middle East to the Pacific to pay their "fair share" of the cost of the alliances.

"And now, based on our very strong and frank discussions, they are beginning to do just that," he said. "In fact, I can tell you the money is pouring in."

Japan's lower house approved on February 27 the budget bill for fiscal 2017 starting on April 1, with the defense spending rising for a fifth straight year to a record 5.1 trillion yen ($45 billion), or 1.4 percent increase from the previous fiscal year.