TV
The 68-year-old will play the character in three new episodes to air next month before filming a final two-parter next year.
"It's time to move on. Frost is getting a little long in the tooth - it's time for Frost to hang up his coat and scarf," Sir David commented at a London press conference.
The actor added that there will not be a dry eye in the house when the inspector solves his last case.
"Perhaps he just retires gracefully, gets the gold watch and walks away from Denton nick, tears all round. He just hangs up his hat," he said.
Last year, Jason signed an exclusive deal with ITV preventing him from working for any other broadcaster.
More: David Jason, TV
Tube Talk
'Being Human': Episode 2 teasersTen tantalising teasers about episode two of the new Being Human.
TV Interviews
Randy Jackson on 'Idol' fainting, pressure: Q&AFive singers faint - and one falls off the stage - on most intense Hollywood Week yet.
Reality Bites
Does Simon Cowell have new SuBo?: VideoWatch a clip of Jonathan Antoine, who is tipped for success on BGT.
TV Ratings
'The Only Way Is Essex' draws nearly 1mBBC One wins primetime with help from Super Smart Animals and MasterChef.
