Former New York City Mayor Rudy Giuliani was hospitalised and was in “critical but stable condition,” his spokesperson said on Sunday.

The spokesperson, Ted Goodman, did not immediately provide more details about Giuliani’s condition or how long he has been hospitalised.

“Mayor Giuliani is a fighter who has faced every challenge in his life with unwavering strength, and he’s fighting with that same strength now,” Goodman said in a statement.

“We do ask that you join us in prayer for America’s Mayor Rudy Giuliani.”

Giuliani, 81, garnered acclaim for his response to the September 11, 2001, al-Qaeda attack on New York City, earning the nickname “America’s Mayor”.

Giuliani worked as an attorney for President Donald Trump in his failed efforts to overturn the results of the 2020 election, an effort that led to criminal charges against Giuliani in two US states and a defamation lawsuit from election workers. Giuliani has denied wrongdoing in the criminal cases.

Trump, in a social media post, called Giuliani the “Best Mayor in the History of New York City” and said he had been mistreated by Democrats.

Giuliani was previously hospitalised last year following a car crash in New Hampshire.