The country music legend Glen Campbell, who has been diagnosed with Alzheimer's disease, is preparing to launch a final tour to say farewell to his fans.

The 75-year old singer, known for hits like Rhinestone Cowboy, Gentle on my Mind and Wichita Lineman, is also releasing an album of new material.

He and his wife Kim said they want everyone to know about Glen's medical condition, to explain any lapses in memory while he is performing.

They said they both wanted to ''enjoy life'' and the singing star added he was living ''one day at a time''.