Florida governor Ron DeSantis has announced an international tour of several key US allies, building momentum for an expected White House bid.

A statement from his office said the Republican presidential hopeful would visit Japan, South Korea, Israel and Britain, announcing the trip as a chance to "expand economic partnerships" for the southern US state.

Japan's foreign ministry said DeSantis would be in Japan on April 24 and 25, and is scheduled to visit Prime Minister Fumio Kishida.

He will also have a working dinner with Japan's Foreign Minister Yoshimasa Hayashi on Monday, the ministry added.

In the battle for the 2024 Republican nomination, DeSantis is the biggest threat to former president Donald Trump, in both polls and media attention.

While the trip was couched solely in terms of business opportunities for Florida, it is likely to be interpreted as an attempt by DeSantis to burnish his diplomatic and national security credentials.

Tokyo and Seoul are both key US allies in Asia, and the United States has more troops stationed in Japan than anywhere else in the world.

Israel is another traditional stop for US presidential candidates, particularly Republicans, and the trans-Atlantic "special relationship" makes London another obvious choice.

The 44-year-old Marine veteran has sought to transform Florida into a laboratory of conservative policy -- easing restrictions on guns, tightening access to abortion, and waging culture wars spanning education policy and LGBTQ rights.

But he has not yet tested his mettle on the national stage, critics say, and Trump still polls ahead of the governor nationally.

DeSantis is also yet to officially throw his hat into the ring, though that has not stopped Trump from regularly attacking him.