A former Olivia Chow advisor who came under fire for accusing mayoral rival John Tory of "segregationist" transit policies is threatening to sue his campaign strategist for libel.

Toronto law firm Shillers LLP tweeted at Tory's strategist Nick Kouvalis Friday afternoon on behalf of Warren Kinsella.

The tweet contained a link to a notice which alleges Kouvalis defamed Kinsella by suggesting in a series of tweets that Chow's campaign was better off without him.

"…don't count (Olivia Chow) out just yet. The campaign made a very smart move dumping Kinsella et al today…" reads one of the tweets mentioned in the notice. It also highlights two tweets that link to a YouTube video of Beyonce's hit "Irreplacable" and a video of AC/DC's "Thunderstruck."

Those tweets were published Thursday night, after Chow said that Kinsella will no longer be involved in her campaign's day-to-day operations.

According to the notice, Kouvalis' tweets were motivated by "malice."

Kouvalis' "conduct was high-handed and callous and demonstrated a total disregard for the truth or Mr. Kinsella's reputation," the libel notice reads.

The libel notice demands that Kouvalis, who was once a strategist for Rob Ford, publish an unequivocal apology and retraction on "Twitter, in a prominent and permanent location." It also demands that he delete the tweets.

The deadline to meet Kinsella's demands is the end of the day on Sept. 3.

Earlier this month, Kinsella suggested in a series of tweets that Tory's transit plan was segregationist. He noted in his tweets -- that have since been deleted -- that Tory's Smart Track plan skips over the Rexdale and Jane-and-Finch neighbourhoods.