US President Donald Trump said no nation should underestimate American resolve, as he arrived in Japan yesterday at the start of a marathon Asian tour.
Addressing US troops at Yokota air base near Tokyo, he pledged to ensure the military had the resources needed to keep peace and defend freedom.
He later told the Japanese prime minister he thought the two countries had never been closer.
It will be the longest tour of Asia by a US president in 25 years.
South Korea, China, Vietnam and the Philippines are also on the itinerary in the coming week.