Former New York City mayor Rudy Giuliani was hospitalized in critical but stable condition, according to a statement by his spokesperson, Ted Goodman, on Sunday night.

The statement didn't specify the reason behind Giuliani's hospitalization, who is 81 years old and a close ally of US President Donald Trump.

“Mayor Giuliani is a fighter who has faced every challenge in his life with unwavering strength, and he’s fighting with that same level of strength as we speak. We do ask that you join us in prayer for America’s Mayor Rudy Giuliani,” read the statement by Goodman.

According to a report by The New York Times, Giuliani was hospitalized in Florida, where he currently resides.

He served as New York City's mayor from 1994 to 2001 and worked as Trump's personal attorney, most recently representing him in lawsuits to overturn the 2020 election results.

Trump confirmed Giuliani's hospitalizations in a Truth Social post, calling him "a true warrior, and the best mayor in the history of New York City, by far."

He also accused the "radical left" of treating him very poorly, implying that it was because of this that he was currently being hospitalized.

"They cheated on the Elections, fabricated hundreds of stories, did anything possible to destroy our nation, and now, look at Rudy," Trump wrote.