The letter is among an array of showbiz memorabilia – made up of 700 lots – found in Morecambe’s former home, Brachefield in Harpenden, Hertfordshire.
Wise wrote: “Well, Eric, I want to get straight to the point. I want us to break up the act. I’m afraid it won’t work.”
Explaining the “terrific amount” of animosity he was feeling at home, he continued: “I feel it would be better if we parted.
“I know this will be quite a shock to you but I had to come to some decision.
“I can’t go on as things are, I’m not satisfied with my work, I have lost a lot of zip and it will take time to regain it.
“I can’t keep you waiting around for me, I don’t know definitely when I will be out. I feel it’s a great pity after we had planned so much, but my mind’s made up.”
He concludes saying he hoped they would remain friends and signs the letter off with “your best pal, Ernie”.
Morecambe’s son Gary said his father had quickly written back, telling Wise he had never heard such rubbish in his life.