North Korea's leader Kim Jong Un speaks during a New Year's Day speech in this photo released by North Korea's Korean Central News Agency (KCNA) in Pyongyang on January 1, 2018.

Three Americans held in a North Korean prison will be released today, Rudy Giuliani, a member of President Trump's legal team, said Thursday.

"We got Kim Jong Un impressed enough to be releasing three prisoners today," the former New York mayor told Fox & Friends.

Giuliani made his proclamation hours after President Trump made reference to the three Americans in a tweet that reflected optimism the case of the Americans would soon be determined.

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"As everybody is aware, the past Administration has long been asking for three hostages to be released from a North Korean Labor camp, but to no avail," Trump tweeted. "Stay tuned!"

The three men — Kim Hak-Song, also known as Jin Xue Song; Tony Kim, also known as Kim Sang-Duk; and Kim Dong-Chul — have been relocated within the secretive nation and are getting medical treatment ahead of the planned release, according to multiple media reports.

The development comes as tensions have eased between the U.S. and North Korea. A meeting between Kim and Trump is in the works, and Trump has said details could be released within days.

The two leaders also have toned down their sharp rhetoric. Trump, who has referred to Kim in the past as "little rocket man," suggested last week that Kim is "very honorable."

Talk of the release also comes less than a week after a historic summit between Kim and South Korean President Moon Jae-in at which Kim pledged to shut down his nuclear testing site within weeks.

Moon and Kim also agreed to work on a plan to formally end the Korean War that was ended under a temporary armistice in 1953. North Korea's leader has said a formal end to the hostilities, along with a pledge from the U.S. not to attack his nation, would essentially eliminate Pyongyang's need for a nuclear arsenal.

Last year, U.S. college student Otto Warmbier died after being imprisoned in North Korea. He was jailed after trying to steal a propaganda sign from a hotel in the country. When he was released in June back to his family, he was in a coma and unresponsive.