US President Donald Trump has mistakenly said the "Islamic Republic of Japan" fired 111 missiles at an American aircraft carrier, misidentifying Iran in remarks that do not match official US military accounts.

Speaking alongside Ukrainian President Volodymyr Zelensky on the sidelines of the NATO summit in Ankara on Jul 8, Trump described the USS Abraham Lincoln as "one of the most beautiful" and "one of the biggest" carriers, USA Today reports.

"A few months ago... we had 111 missiles shot by the Islamic Republic of Japan," he said, adding that the missiles were fired at the carrier over about an hour and all were intercepted.

No country by the name "Islamic Republic of Japan" exists. Iran's official name is the Islamic Republic of Iran.

Japan and the US, meanwhile, have been treaty allies since 1952, with around 60,000 American troops currently based in the East Asian country.