Williamson, who acts as an executive producer on the two CW series, told audiences at San Diego Comic-Con that fans of The Vampire Diaries will also appreciate The Secret Circle.
"If you like The Vampire Diaries, this is a show you will enjoy just as well," Williamson said of The Secret Circle.
However, he went on to promise that the two series are very different, saying that a crossover between the shows will never happen.
Williamson explained: "They're two different worlds. They're from the same novelist but the worlds don't intersect. This is witches; there's a huge mythology that doesn't connect to Bonnie and The Vampire Diaries. This is a brand new story."
He has previously confirmed that the two CW series will remain separate in April, adding that he will primarily focus on The Vampire Diaries.
In early July, Williamson hinted that Vampire Diaries viewers will receive answers regarding Jeremy's haunting in an October episode of the show.
In the second season finale, Jeremy (Steven McQueen) was killed and brought back to life with the ability to see his dead ex-girlfriends Vicki (Kayla Ewell) and Anna (Malese Jow).
Watch a 'first look' trailer for The Secret Circle from Comic-Con 2011 below: