Professor Mary Beard has apologised for her comments about “B-list actors” appearing in “excruciating” historical reconstructions.

The broadcaster and classicist, 63, said she only agrees to front TV documentaries if there is a ban on anyone dressing up in period costume.

She said she always demanded that there would be “no drama reconstructions in any programme made by me, no B-list actors dressed up in sheets, saying ‘do pass the grapes Marcus’.”

Prof Beard has now apologised for the comments and said she was trying to “rescue” performers from having to learn “dumb dialogue”.

She wrote on Twitter: “my reference to ‘b list’ actors has been given more headlines than a single throwaway deserves. Sincere apologies to all actors, struggling and otherwise (perhap in (sic) shd say I was trying to rescue you from having to dress up in sheets and learn some dumb dialogue!).”

The comments were included in a speech the academic was due to give at the Jocelyn Hay Lecture 2018 on Tuesday.

Prof Beard said she will never again allow text from a lecture to be released ahead of her giving it.

She tweeted: “One thing I’ve learned today is never ever let text of a lecture be circulated in advance.

“The irony & the jokes that are ok and can be acknowledged in oral delivery do not translate to the page! And excerpts even if accurate can be almost guaranteed to give wrong impression.”