Muhammad Ali's condition has "vastly improved" since being admitted to a US hospital on Saturday with a mild case of pneumonia and his doctors are hopeful that he will soon be sent home, his representatives Boxcar have announced.

The 72-year-old, who suffers from Parkinson's disease, was taken to an undisclosed location on Saturday morning.

"Muhammad Ali has vastly improved since being admitted to the hospital over the weekend with a mild case of pneumonia," the statement read.

"Ali's team of doctors hopes to discharge him soon.

"The Ali family continues to request privacy and appreciates all of the prayers and well wishes.

"No further details are being released."

Ali, considered by many to be the greatest boxer of all time, retired from the sport in 1981 and has suffered with Parkinson's since the mid-1980s.

Ali last appeared in public in September when he attended the Muhammad Ali Humanitarian Awards in Louisville, Kentucky where he keeps a home.