“It was one of the most disgusting performances in public life that I can remember.”
"It’s a metaphor for an entire year of Covid incompetence," he told Question Time.
The BBC panel show's team captain said critics believe they are “Momentum-inspired, lefty lunatics”.
The satirical panel show debuted on BBC Two on 28 September 1990.
The PM's chief advisor was the subject of a "pitch perfect" monologue from the journalist and broadcaster.
The Netflix series' creator hosted the BBC panel show on Friday.
"Go out in the garden, have a bit of sunshine, and stop believing complete rubbish," the Have I Got News For You panellist said.
The topical BBC panel show has had to adapt due to social distancing rules.
Have I Got News For You descended into a tense row over Mercer's alleged links to a bust financial firm.
'Unless Ann Widdecombe has put off an entire gender, it's because they’ve said no.'