Clunes reached 12 points on his licence for four speeding offences and has been banned by magistrates under "totting up" rules.
A spokesman for Churchill said: "Martin Clunes recently informed Churchill Insurance that his driving licence has been suspended after he accumulated penalty points for four speeding offences.
''Churchill Insurance currently has no adverts with Martin Clunes on air and will be moving forward with new advertising in the New Year.''
The spokesman declined to reveal whether the new campaign would feature a celebrity but confirmed that the brand would still be working with ad agency WCRS.
Clunes, who first appeared in a Churchill ad on Boxing Day 2011, is the latest celebrity the brand’s nodding dog character has outlasted.
The ads featured Vic Reeves as the voice of the dog until 2005, when he was arrested and charged with drink-driving and leaving the scene of an accident.
The brand used several different celebrities before introducing Clunes, including Rolf Harris, Roy Walker, Melanie Sykes and Ricky Hatton.
Churchill appeared to be happy with the longer-term relationship with Clunes, who marketing director Amanda Walker, in December 2011, described as "highly credible".
She said: "Consumers have grown up with him, so he lends extra trust to the campaign. [Clunes] is in every frame of the ad, so rather than Churchill interacting with lots of celebrities, there is one key relationship."Follow @DanFareyJones