She said it was “a little bit more controversial every year”.
“It’s harder to decide what is appropriate, what the backlash is going to be, that bit is quite hard,” she added.
Chair of the bonfire society, Bill Cummings said: “We hold everyone to account and we’ll burn anyone, no matter how important.
“We torched an effigy of Liz Truss a few years ago and the lettuce on her shoulder wouldn’t light, so we now have someone bearing it at the very front of our procession.”
The not-for-profit organisation has been celebrating Bonfire Night for nearly 100 years.
The 11m effigy of Sir Keir will take centre stage on Saturday, alongside a giant Guy Fawkes.