The Mighty Boosh star will be a regular guest on Vic Reeves’ House Arrest, when it starts on Radio 2 next month.
The premise is that Reeves has been put under house arrest for a ‘wacky’ crime he didn’t commit and he's forced to spend the day killing time.
Fielding will play a strange odd-job man, while Mortimer will play Carl The Hairdresser. Regular strands in the show, which starts on November 17, include Reeves trying to get on to X Factor by singing in the bath.
Meanwhile, Reeves has today been named a legend by Loaded magazine.
He is comedian to win the annual honour in the lads’ mag Lafta comedy awards, following actors Ricky Tomlinson and Leslie Phillips, and entertainer Bruce Forsyth.
Reeves said: ‘It's the most fantastic thing ever. I've won three Baftas and numerous other awards but there comes a time in a man's life when he needs to look back and this is the best.’
Loaded editor Martin Daubney added: ‘Vic Reeves is a legend in every sense of the word. He's one of the funniest fellas this country has ever seen and is totally deserving of this award.’
The rest of the winners are revealed on Thursday.
