Legendary evangelist Billy Graham is reportedly very weak following his hospitalisation last year.

Reverend Franklin Graham requested prayers for his father during a brief talk with WBTV's Coleen Harry on January 17.

Reverend Franklin stated that his father is doing "just okay" but remains weak. "His vitals are good, but [he] just does not have strength," Franklin told WBTV. "For those that are watching, my father would appreciate your prayers."

Franklin Graham told the news station: "My father is ready to go to Heaven and whenever that day comes - he's ready," Franklin Graham said.

"He's worked hard all of his life and faithful to preaching the Gospel of Jesus Christ his entire life. And so he's ready to go home and I'm praying that The Lord will leave him a little longer.

"He knows when I'm in the room. He recognises me. He'll say a few words to me but to be able to carry on a conversation - it's been difficult since Christmas.

"We need him. He's a great father, been a great friend and just [pause] I enjoy having lunch with him every Sunday," he told WBTV. "I have my own personal reason for wanting him to stay around a long time."

Franklin Graham said he is praying for him to get his strength back and that "it be God's will that he can get his strength back because we still have some work for him to do."

The 95-year-old was admitted to the Mission Hospital in Asheville, North Carolina on November 20 with a respiratory congestion issue. Prior to the hospitalisation, Graham was taken to hospital at the end of October for a routine check-up.

Graham, known as "America's Pastor", released what may be his final public video message on his 95^th birthday on November 7, 2013.

After decades of preaching, Graham released a DVD in an evangelical effort called "My Hope America, with Billy Graham" to reach people across the United States with the Gospel of Jesus Christ. In the message, he said, "Our country's in great need of a spiritual awakening...There have been times that I've wept as I've gone from city to city and I've seen how far people have wandered from God."

The retired evangelist has preached to millions of people in 185 countries worldwide over his lifetime.