Actor Michael Clarke Duncan has left an intensive care unit nearly a month after suffering a heart attack bur still remains in the hospital despite making progress in his health.

Publicist Joy Fehily said in a brief email statement that the 54-year-old actor "was just moved from the intensive care unit, but remains hospitalised" following his July 13 heart attack.

"His family are firm believers in the power of prayer and have asked that you keep him in yours during this time."

No further information was available on Duncan's condition.

Duncan – best known for playing John Coffey in the 1999 Tom Hanks movie The Green Mile, suffered the myocardial infarction in July.

He reportedly was found by his girlfriend of two years, The Apprentice contestant Omarosa Stallworth.

His 38-year-old partner performed CPR and revived him.

She recently tweeted: "Everyday GOD continues to smile upon my luv Michael Clarke Duncan on this arduous road to recovery. God is with us every step of the way!!"

Duncan’s appearance in The Green Mile saw him nominated for a host of accolades including an Academy Award and a Golden Globe, both for Best Supporting Actor, as well as Screen Actors Guild Award nomination for Outstanding Performance by a Male Actor in a Supporting Role.

He acted in blockbuster Armageddon in 1998, but his relatively small but comic role was eclipsed by Bruce Willis, Ben Afleck and Liv Tyler.

Since The Green Mile, however, Duncan shot to stardom and went on to star in numerous motion pictures including The Whole Nine Yards, Planet of the Apes, Sin City, Daredevil, The Scorpion King and Kung Fu Panda.