US President Donald Trump and Japanese Prime Minister Shinzo Abe on Tuesday jointly inspected Japan's largest warship south of Tokyo at the Yokosuka-based Japan Maritime Self-Defense Force.

Aboard the Japanese J.S. Kaga destroyer, a helicopter carrier designed to carry submarine-hunting helicopters to distant waters, Trump, winding up his four-day state visit to Japan, made a joint speech with Abe to address some 500 Japanese and US personnel inside the warship's hangar.

"I want to thank my friend, and your prime minister. He's an extraordinary man, for his commitment to improving Japan's defense capabilities which also advances the security of the United States of America," Trump said.

The US president also thanked Japan for planning to buy more US-made 5th generation F-35B stealth fighter jets.

Before heading home from Japan on Tuesday afternoon, Trump will also land aboard the USS Wasp, a US multipurpose amphibious assault ship, where he'll deliver a Memorial Day speech to US troops.